Momentum Practice Problems - Weebly · 2018-09-04 · Momentum Practice Problems PSI AP Physics C...
Transcript of Momentum Practice Problems - Weebly · 2018-09-04 · Momentum Practice Problems PSI AP Physics C...
Momentum Practice Problems
PSI AP Physics C Name________________________________ Multiple Choice
1 A steel ball and a piece of clay have equal mass They are dropped from the same height on a horizontal steel platform The ball bounces back with nearly the same speed with which it hit The clay sticks to the platform Which object experiences the greater momentum change
(A) the ball (B) the clay (C) Both experience the same momentum change (D) there is no momentum change for either (E) more information is required
2 A car of mass m is moving with a momentum p How would you represent its kinetic energy in terms of these two quantities
(A) p2(2m) (B) 12 mp2 (C) mp (D) mp2 (E) zero
3 A bowling ball moving with speed v collides head-on with a stationary tennis ball The collision is elastic and there is no friction The bowling ball barely slows down What is the speed of the tennis ball after the collision
(A) nearly v (B) nearly 2v (C) nearly 3v (D) nearly infinite (E) Zero
4 An object with a mass of 2 kilograms is accelerated from rest The graph shows the magnitude of the net force as a function of time At t=4 seconds the objectrsquos velocity would have been closest to which of the following
(A) 2 ms (B) 4 ms (C) 10 ms
(D) 13 ms (E) 20 ms
5 A 3 kg ball is dropped onto a concrete floor
What is the magnitude of the ballrsquos change in
momentum if its speed just before striking the floor is 7 ms and its rebound speed is 3
ms
(A) 10 kg ms (B) 15 kg ms (C) 30 kg ms (D) 50 kg ms
(E) 70 kg ms
Questions 6 - 8
6 Two blocks are on a frictionless surface and have the same mass m Block 2 is initially at rest Block 1 moves to the left with speed 4v Block 1 collides inelastically with block 2 Which of the following choices is closest to the final speed of the system of two blocks
(A) v (B) 2v (C) 3v (D) 4v (E) 5v
7 Two blocks are on a frictionless surface and have the same mass m Block 2 is initially at rest Block 1 moves to the left with speed 4v Block 1 collides elastically with block 2 What is the final speed of block 1
(A) zero (B) v (C) 2v (D) 3v (E) 4v
8 Two blocks are on a frictionless surface and have the same mass m Block 2 is initially at rest Block 1 moves to the left with speed 4v Block 1 collides elastically with block 2 What is the final speed of block 2
(A) v (B) 2v (C) 3v (D) 4v (E) 6v
Questions 9-10
9 A hockey stick hitting a 05 kg puck is in contact with the ball for a time of 05 seconds
The puck travels in a straight line as it approaches and then leaves the hockey stick If
the puck arrives at the stick with a velocity of 64 ms and leaves with a velocity of -36
ms What is the magnitude of the change in momentum of the puck
(A) 2 kgms (B) 3 kgms (C) 5 kgms (D) 6 kgms (E) 10 kgms
10 A hockey stick hitting a 05 kg puck is in contact with the ball for a time of 05 seconds
The puck travels in a straight line as it approaches and then leaves the hockey stick If
the puck arrives at the stick with a velocity of 64 ms and leaves with a velocity of -36
ms what is the magnitude of the average force acting on the puck
(A) 100 N (B) 150 N (C) 200 N (D) 300 N (E) 500N
Questions 11-12
11 An object of mass 3 kg starts from rest and
moves along the x-axis A net horizontal force
is applied to the object in +x direction The
force time relations presented by the graph
What is the net impulse delivered by this
force
(A) 6 Ns (B) 8 Ns (C) 24 Ns
(D) 30 Ns (E) 36 Ns
12 An object of mass 3 kg starts from rest and moves along the x-axis A net horizontal
force is applied to the object in +x direction The force time relations presented by the
graph What is the net work done on the object
(A) 30 J (B) 50 J (C) 90 J (D) 150 J (E) 120 J
13 A tennis ball of mass m rebounds from a vertical wall with the
same speed v as it had initially What is the change in
momentum of the ball
(A) mv (B) 2mv (C) 2mvcosθ
(D) 2mvsinθ (E) zero
14 A steel ball moving at a constant speed v on a horizontal frictionless surface collides obliquely with an identical ball initially at rest The velocity of the first ball before and after the collision is presented on the diagram What is the approximate direction of the velocity of the second ball after the collision
(A) (B) (C)
(D) (E)
Questions 15-16
15 A stationary cannon ball explodes in three pieces of masses m m and 2m The two
momenta of equal masses presented by the diagram What is the direction of the
momentum of 2m mass
(A) (B) (C) (D) (E)
16 What is the magnitude of the velocity of 2m cannon ball piece
(A) radic2
2119907 (B)
radic3
2119907 (C)
radic5
2119907 (D)
1
2119907 (E)
3
2119907
17 An object with an initial momentum shown on the diagram collides with another object at
rest Which of the following combinations of two vectors may represent the momenta of
the two objects after the collision
(A) (B) (C)
(D) (E)
Questions 18-19
A 6 kg block moves with a constant speed 5 ms on a horizontal frictionless surface and
collides elastically with an identical block initially at rest The second block collides and
sticks to the last 6 kg block initially at rest
18 What is the speed of the second 6 kg block after the first collision
(A) zero (B) 2 ms (C) 25 ms (D) 3 ms (E) 5 ms
19 What is the speed of the third 6 kg block after the second collision
(A) zero (B) 2 ms (C) 25 ms (D) 3 ms (C) 5 ms
Questions 20-21
Object A with mass 8 kg travels to the east at 10 ms and object B with mass 3 kg travels south
at 20 ms The two objects collide and stick together
20 What is the magnitude of the velocity they have after
the collision
(A) 18 ms (B) 91 ms (C) 127 ms
(D) 20 ms (E) 255 ms
21 What is the direction of the velocity they have after the
collision
(A) 30ordm south of east (B) 37ordm south of east
(C) 45ordm south of east (D) 53ordm south of east
(E) 60ordm south of east
22 Two balls of equal mass m move with equal speeds v along paths inclined at 30deg
from the horizontal as shown After the collision they stick together What is the
magnitude of their velocity
(A) radic2 v (B) 119907
2 (C)
radic2119907
2 (D)
radic3119907
2 (E) v
23 Block m1 is moving with speed vo toward stationary block m2 collides and sticks with it The speed of the center of mass of the system is
(A) 1198981
1198982119907119900 (B)
1198982+1198981
1198982119907119900 (C)
1198982+1198981
1198981119907119900 (D) (1 + 1198981)119907119900
(E) 1198981
1198981+1198982119907119900
24 A cannonball of mass 2m is moving towards the right with initial velocity vo and explodes into two equal pieces each with mass m What is the speed of the center of mass after the explosion
(A) vo (B) 05 vo (C) 2 vo (D) 4 vo (E) 0
25 A bullet of mass M1 is fired from a gun that is initially at rest The combined mass of the gun and bullet is M2 If after the bullet is fired its kinetic energy is KE what is the kinetic energy of the gun when it recoils
(A) KE (B) 1198722
1198721119870119864 (C)
11987212
11987222119870119864 (D)
1198721
1198722minus1198721119870119864 (E) radic
1198721
1198722minus1198721119870119864
26 A ball of mass m is moving to the right with speed 3v on a frictionless tabletop when it collides with a second ball of mass 3m that is moving to the right with speed v If the two balls stick together upon impact the speed of the balls immediately after the collision is
(A) v3 (B) v2 (C) 2v3 (D) 3v2 (E) 2v
27 Person A and Person B are standing on a sheet of frictionless ice Person A pushes Person B so that Person B who is 60 kg moves to the right at 3 ms while Person A who is 90 kg moves to the left at 2 ms What is the velocity of their center of mass
(A) Zero (B) 05 ms to the left (C) 1 ms to the right
(D) 24 ms to the left (E) 25 ms to the right
28 What is the rebound speed of a 4 kg ball falling straight down that hits the platform at 4 ms if the average normal force exerted by the platform on the ball was 40 N for 05s
(A) 2 ms (B) 7 ms (C) 6 ms (D) 9 ms (E) 1 ms
29 A 2 kg mass moving at 12 ms collides with an identical mass moving at -8 ms and the mass stick together What is the final velocity of the two masses
(A) 43 ms (B) 2 ms (C) 6 ms (D) 10 ms (E) 12 ms
30 A compressed spring is placed between two masses M and m resting on a smooth horizontal surface When the spring is released the two fly apart with M moving at velocity v The velocity of m is
(A) 119872
119898119907 (B) minus
119872
119898119907 (C)
119898
119872119907 (D) minus
119898
119872119907 (E)
119898
119898+119872119907
31 Consider these two cases First a car moving at 40 mph hits another car of equal mass moving at 40 mph in the opposite direction
Second a car moving at 40 mph hits a stationary steel wall
The collision time is the same for the two cases and the collisions are both inelastic In which of these cases would result in the greatest impact force
(A) Hitting the wall (B) Hitting the other car (C) The force would be the same in both cases (D) More information is needed (E)None of the above are true
Questions 32-33
A mass M moving with speed v collides with an uncompressed stationary spring of mass M with a spring constant K The surface is frictionless
32 What will be the maximum compression of the spring
(A) vradic119872119870 (B) vradic1198724119870 (C) 119907
2 radic3119872119870 (D) vradic2119872119870 (E) vradic1198722119870
33 What is the speed of the spring after the collision
(A) v (B) 119907 2frasl (C) 119907 4frasl (D) 2v (E) 119907 3frasl
Questions 34-35
A 6 kg mass is moving at 12 ms in the +x direction is acted upon by a force with magnitude given as a function of time by the graph
34 Find the magnitude of the change in momentum from time t = 0 to time t = 8 s
(A) 12 kg ms (B) 24 kg ms (C) 36 kg ms (D) 40 kg ms (E) 52 kg ms
35 What is the velocity of the mass after the force has stopped acting
(A) 6 ms (B) 10 ms (C) 18 ms (D) 24 ms (E) 40 ms
36 A wire is bent into the shape as shown above Which of the following best represents the coordinates of the center of mass
(A) (1314 67) (B) (87 67) (C) (1314 87) (D) (11) (E) (167)
37 A block of mass m is moving with speed vo to the right on a frictionless surface when it explodes into two pieces of unequal mass One piece of the mass 3m4 moves with a speed vo2 to the left while the other piece of the object moves with velocity
(A) vo2 (B) 2vo3 (C) 11vo2 (D) 7vo5 (E) 2vo
38 Two blocks with masses m and 2m are placed on a horizontal frictionless surface There is a compressed spring between the block and after the spring is released 2m block moves to the right with a speed of v What is the total work done by the spring on the system of two blocks
(A) Zero (B) mv2 (C) 2mv2 (D) 3mv2 (E) mv
39 A railway artillery gun of mass 1400 tonnes is initially at rest on a horizontal surface when fires a 7 tonnes shell with a velocity of 800 ms at an angle of 60deg What is the speed of the gun immediately after the shell is fired
(A) Zero (B) 2 ms (C) 4 ms (D) 5 ms (E) 7 ms
40 Two equal forces are exerted for the same length of time on two blocks with different masses m1 and m2 (m2 gtm1) Which of the following will describe the change is kinetic energy of the blocks
(A) Blocks have the same change in kinetic energy
(B) The change in kinetic energy of each block is zero
(C) Block m2 has greater change in kinetic energy
(D) Block m1 has greater change in kinetic energy
(E) Non from the above is correct
41 A boy launches a 20 g dart in horizontal by a spring gun from a balcony 45 m above the ground The dart lands 15 m away from the balcony If the length of the gunrsquos barrel is 10 cm what is the average horizontal force applied by the spring
(A) 10 N (B) 20 N (C) 25 N (D) 50 N (E) 75 N
42 A mall of mass m is dropped from a height of ho The ball hits the floor and bounces to a height of h What is the magnitude of impulse exerted on the ball by the floor
(A) mgh (B) 2mgh (C) radic2119898119892ℎ (D) 119898radic2119892(ℎ minus ℎ119900) (E) 119898radic2119892(ℎ + ℎ119900)
43 A 5 kg object starts from rest on a flat horizontal surface and moves in a straight line The velocity as a function of time is given by v = 3t + 2t2 What is the magnitude of instantaneous force that acts on the object at 2 s
(A) 105 N (B) 75 N (C) 55 N (D) 45 N (E) 35 N
44 A net force F = 10 + 6t2 is applied to a 30 kg cart that can move on a flat horizontal surface If the cart starts from rest what is its speed at 5 s
(A) 10 ms (B) 8 ms (C) 5 ms (D) 3 ms (E) 1 ms
45 Block of mass m moves to the right at a constant velocity v and collides elastically with another block of mass 3m Which of the following is the velocity of each block after the collision
Block m Block 3m
(A) Zero v
(B) v2 v2
(C) ndashv2 v2
(D) 3v2 v2
(E) ndashv2 3v2
46 A 40 kg skateboarder runs at a constant velocity of 12 ms and jumps of a
stationary skateboard with a mass of 8 kg What is the velocity of the
skateboard after the jump
(A) 12 ms (B) 90 ms (C) 60 ms (D) 20 ms (E) 10 ms
47 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves
at a constant velocity of 2 ms What is the velocity of the boat after the jump if the
diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the
boat
(A) 2 ms (B) 3 ms (C) 4 ms (D) 5 ms (E) 6 ms
48 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back
with a momentum of 6 kgms after the collision with the racket What is the change
in momentum of the tennis ball
(A) 1 kgms (B) 5 kgms (C) 6 kgms (D) 11 kgms 0 kgms
49 A light beach ball moving with a velocity 2 ms to the right collides elastically with a
stationary bowling ball After the collision the bowling ball remains stationary What is
the velocity of the beach ball after the collision
(A) 0 ms (B) 2 ms to the left (C) 4 ms to the left
(D) 3 ms to the left (E) 1 ms to the left
50 A of mass m moving at a constant speed v to the right collides elastically with
another ball of mass 3m moving to the left at a constant speed v What is the velocity
of ball m after the collision
(A) v (B) minus3
2v (C) minus
1
3v (D) 2v (E) -2v
Answer Key
1A 6B 11D 16A 21B 26D 31C 36A 41C 46E
2A 7A 12D 17E 22D 27A 32E 37C 42E 47B
3B 8D 13C 18E 23E 28E 33A 38D 43C 48D
4A 9C 14C 19C 24A 29B 34C 39B 44A 49B
5C 10A 15B 20B 25D 30B 35C 40D 45C 50E
Questions 6 - 8
6 Two blocks are on a frictionless surface and have the same mass m Block 2 is initially at rest Block 1 moves to the left with speed 4v Block 1 collides inelastically with block 2 Which of the following choices is closest to the final speed of the system of two blocks
(A) v (B) 2v (C) 3v (D) 4v (E) 5v
7 Two blocks are on a frictionless surface and have the same mass m Block 2 is initially at rest Block 1 moves to the left with speed 4v Block 1 collides elastically with block 2 What is the final speed of block 1
(A) zero (B) v (C) 2v (D) 3v (E) 4v
8 Two blocks are on a frictionless surface and have the same mass m Block 2 is initially at rest Block 1 moves to the left with speed 4v Block 1 collides elastically with block 2 What is the final speed of block 2
(A) v (B) 2v (C) 3v (D) 4v (E) 6v
Questions 9-10
9 A hockey stick hitting a 05 kg puck is in contact with the ball for a time of 05 seconds
The puck travels in a straight line as it approaches and then leaves the hockey stick If
the puck arrives at the stick with a velocity of 64 ms and leaves with a velocity of -36
ms What is the magnitude of the change in momentum of the puck
(A) 2 kgms (B) 3 kgms (C) 5 kgms (D) 6 kgms (E) 10 kgms
10 A hockey stick hitting a 05 kg puck is in contact with the ball for a time of 05 seconds
The puck travels in a straight line as it approaches and then leaves the hockey stick If
the puck arrives at the stick with a velocity of 64 ms and leaves with a velocity of -36
ms what is the magnitude of the average force acting on the puck
(A) 100 N (B) 150 N (C) 200 N (D) 300 N (E) 500N
Questions 11-12
11 An object of mass 3 kg starts from rest and
moves along the x-axis A net horizontal force
is applied to the object in +x direction The
force time relations presented by the graph
What is the net impulse delivered by this
force
(A) 6 Ns (B) 8 Ns (C) 24 Ns
(D) 30 Ns (E) 36 Ns
12 An object of mass 3 kg starts from rest and moves along the x-axis A net horizontal
force is applied to the object in +x direction The force time relations presented by the
graph What is the net work done on the object
(A) 30 J (B) 50 J (C) 90 J (D) 150 J (E) 120 J
13 A tennis ball of mass m rebounds from a vertical wall with the
same speed v as it had initially What is the change in
momentum of the ball
(A) mv (B) 2mv (C) 2mvcosθ
(D) 2mvsinθ (E) zero
14 A steel ball moving at a constant speed v on a horizontal frictionless surface collides obliquely with an identical ball initially at rest The velocity of the first ball before and after the collision is presented on the diagram What is the approximate direction of the velocity of the second ball after the collision
(A) (B) (C)
(D) (E)
Questions 15-16
15 A stationary cannon ball explodes in three pieces of masses m m and 2m The two
momenta of equal masses presented by the diagram What is the direction of the
momentum of 2m mass
(A) (B) (C) (D) (E)
16 What is the magnitude of the velocity of 2m cannon ball piece
(A) radic2
2119907 (B)
radic3
2119907 (C)
radic5
2119907 (D)
1
2119907 (E)
3
2119907
17 An object with an initial momentum shown on the diagram collides with another object at
rest Which of the following combinations of two vectors may represent the momenta of
the two objects after the collision
(A) (B) (C)
(D) (E)
Questions 18-19
A 6 kg block moves with a constant speed 5 ms on a horizontal frictionless surface and
collides elastically with an identical block initially at rest The second block collides and
sticks to the last 6 kg block initially at rest
18 What is the speed of the second 6 kg block after the first collision
(A) zero (B) 2 ms (C) 25 ms (D) 3 ms (E) 5 ms
19 What is the speed of the third 6 kg block after the second collision
(A) zero (B) 2 ms (C) 25 ms (D) 3 ms (C) 5 ms
Questions 20-21
Object A with mass 8 kg travels to the east at 10 ms and object B with mass 3 kg travels south
at 20 ms The two objects collide and stick together
20 What is the magnitude of the velocity they have after
the collision
(A) 18 ms (B) 91 ms (C) 127 ms
(D) 20 ms (E) 255 ms
21 What is the direction of the velocity they have after the
collision
(A) 30ordm south of east (B) 37ordm south of east
(C) 45ordm south of east (D) 53ordm south of east
(E) 60ordm south of east
22 Two balls of equal mass m move with equal speeds v along paths inclined at 30deg
from the horizontal as shown After the collision they stick together What is the
magnitude of their velocity
(A) radic2 v (B) 119907
2 (C)
radic2119907
2 (D)
radic3119907
2 (E) v
23 Block m1 is moving with speed vo toward stationary block m2 collides and sticks with it The speed of the center of mass of the system is
(A) 1198981
1198982119907119900 (B)
1198982+1198981
1198982119907119900 (C)
1198982+1198981
1198981119907119900 (D) (1 + 1198981)119907119900
(E) 1198981
1198981+1198982119907119900
24 A cannonball of mass 2m is moving towards the right with initial velocity vo and explodes into two equal pieces each with mass m What is the speed of the center of mass after the explosion
(A) vo (B) 05 vo (C) 2 vo (D) 4 vo (E) 0
25 A bullet of mass M1 is fired from a gun that is initially at rest The combined mass of the gun and bullet is M2 If after the bullet is fired its kinetic energy is KE what is the kinetic energy of the gun when it recoils
(A) KE (B) 1198722
1198721119870119864 (C)
11987212
11987222119870119864 (D)
1198721
1198722minus1198721119870119864 (E) radic
1198721
1198722minus1198721119870119864
26 A ball of mass m is moving to the right with speed 3v on a frictionless tabletop when it collides with a second ball of mass 3m that is moving to the right with speed v If the two balls stick together upon impact the speed of the balls immediately after the collision is
(A) v3 (B) v2 (C) 2v3 (D) 3v2 (E) 2v
27 Person A and Person B are standing on a sheet of frictionless ice Person A pushes Person B so that Person B who is 60 kg moves to the right at 3 ms while Person A who is 90 kg moves to the left at 2 ms What is the velocity of their center of mass
(A) Zero (B) 05 ms to the left (C) 1 ms to the right
(D) 24 ms to the left (E) 25 ms to the right
28 What is the rebound speed of a 4 kg ball falling straight down that hits the platform at 4 ms if the average normal force exerted by the platform on the ball was 40 N for 05s
(A) 2 ms (B) 7 ms (C) 6 ms (D) 9 ms (E) 1 ms
29 A 2 kg mass moving at 12 ms collides with an identical mass moving at -8 ms and the mass stick together What is the final velocity of the two masses
(A) 43 ms (B) 2 ms (C) 6 ms (D) 10 ms (E) 12 ms
30 A compressed spring is placed between two masses M and m resting on a smooth horizontal surface When the spring is released the two fly apart with M moving at velocity v The velocity of m is
(A) 119872
119898119907 (B) minus
119872
119898119907 (C)
119898
119872119907 (D) minus
119898
119872119907 (E)
119898
119898+119872119907
31 Consider these two cases First a car moving at 40 mph hits another car of equal mass moving at 40 mph in the opposite direction
Second a car moving at 40 mph hits a stationary steel wall
The collision time is the same for the two cases and the collisions are both inelastic In which of these cases would result in the greatest impact force
(A) Hitting the wall (B) Hitting the other car (C) The force would be the same in both cases (D) More information is needed (E)None of the above are true
Questions 32-33
A mass M moving with speed v collides with an uncompressed stationary spring of mass M with a spring constant K The surface is frictionless
32 What will be the maximum compression of the spring
(A) vradic119872119870 (B) vradic1198724119870 (C) 119907
2 radic3119872119870 (D) vradic2119872119870 (E) vradic1198722119870
33 What is the speed of the spring after the collision
(A) v (B) 119907 2frasl (C) 119907 4frasl (D) 2v (E) 119907 3frasl
Questions 34-35
A 6 kg mass is moving at 12 ms in the +x direction is acted upon by a force with magnitude given as a function of time by the graph
34 Find the magnitude of the change in momentum from time t = 0 to time t = 8 s
(A) 12 kg ms (B) 24 kg ms (C) 36 kg ms (D) 40 kg ms (E) 52 kg ms
35 What is the velocity of the mass after the force has stopped acting
(A) 6 ms (B) 10 ms (C) 18 ms (D) 24 ms (E) 40 ms
36 A wire is bent into the shape as shown above Which of the following best represents the coordinates of the center of mass
(A) (1314 67) (B) (87 67) (C) (1314 87) (D) (11) (E) (167)
37 A block of mass m is moving with speed vo to the right on a frictionless surface when it explodes into two pieces of unequal mass One piece of the mass 3m4 moves with a speed vo2 to the left while the other piece of the object moves with velocity
(A) vo2 (B) 2vo3 (C) 11vo2 (D) 7vo5 (E) 2vo
38 Two blocks with masses m and 2m are placed on a horizontal frictionless surface There is a compressed spring between the block and after the spring is released 2m block moves to the right with a speed of v What is the total work done by the spring on the system of two blocks
(A) Zero (B) mv2 (C) 2mv2 (D) 3mv2 (E) mv
39 A railway artillery gun of mass 1400 tonnes is initially at rest on a horizontal surface when fires a 7 tonnes shell with a velocity of 800 ms at an angle of 60deg What is the speed of the gun immediately after the shell is fired
(A) Zero (B) 2 ms (C) 4 ms (D) 5 ms (E) 7 ms
40 Two equal forces are exerted for the same length of time on two blocks with different masses m1 and m2 (m2 gtm1) Which of the following will describe the change is kinetic energy of the blocks
(A) Blocks have the same change in kinetic energy
(B) The change in kinetic energy of each block is zero
(C) Block m2 has greater change in kinetic energy
(D) Block m1 has greater change in kinetic energy
(E) Non from the above is correct
41 A boy launches a 20 g dart in horizontal by a spring gun from a balcony 45 m above the ground The dart lands 15 m away from the balcony If the length of the gunrsquos barrel is 10 cm what is the average horizontal force applied by the spring
(A) 10 N (B) 20 N (C) 25 N (D) 50 N (E) 75 N
42 A mall of mass m is dropped from a height of ho The ball hits the floor and bounces to a height of h What is the magnitude of impulse exerted on the ball by the floor
(A) mgh (B) 2mgh (C) radic2119898119892ℎ (D) 119898radic2119892(ℎ minus ℎ119900) (E) 119898radic2119892(ℎ + ℎ119900)
43 A 5 kg object starts from rest on a flat horizontal surface and moves in a straight line The velocity as a function of time is given by v = 3t + 2t2 What is the magnitude of instantaneous force that acts on the object at 2 s
(A) 105 N (B) 75 N (C) 55 N (D) 45 N (E) 35 N
44 A net force F = 10 + 6t2 is applied to a 30 kg cart that can move on a flat horizontal surface If the cart starts from rest what is its speed at 5 s
(A) 10 ms (B) 8 ms (C) 5 ms (D) 3 ms (E) 1 ms
45 Block of mass m moves to the right at a constant velocity v and collides elastically with another block of mass 3m Which of the following is the velocity of each block after the collision
Block m Block 3m
(A) Zero v
(B) v2 v2
(C) ndashv2 v2
(D) 3v2 v2
(E) ndashv2 3v2
46 A 40 kg skateboarder runs at a constant velocity of 12 ms and jumps of a
stationary skateboard with a mass of 8 kg What is the velocity of the
skateboard after the jump
(A) 12 ms (B) 90 ms (C) 60 ms (D) 20 ms (E) 10 ms
47 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves
at a constant velocity of 2 ms What is the velocity of the boat after the jump if the
diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the
boat
(A) 2 ms (B) 3 ms (C) 4 ms (D) 5 ms (E) 6 ms
48 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back
with a momentum of 6 kgms after the collision with the racket What is the change
in momentum of the tennis ball
(A) 1 kgms (B) 5 kgms (C) 6 kgms (D) 11 kgms 0 kgms
49 A light beach ball moving with a velocity 2 ms to the right collides elastically with a
stationary bowling ball After the collision the bowling ball remains stationary What is
the velocity of the beach ball after the collision
(A) 0 ms (B) 2 ms to the left (C) 4 ms to the left
(D) 3 ms to the left (E) 1 ms to the left
50 A of mass m moving at a constant speed v to the right collides elastically with
another ball of mass 3m moving to the left at a constant speed v What is the velocity
of ball m after the collision
(A) v (B) minus3
2v (C) minus
1
3v (D) 2v (E) -2v
Answer Key
1A 6B 11D 16A 21B 26D 31C 36A 41C 46E
2A 7A 12D 17E 22D 27A 32E 37C 42E 47B
3B 8D 13C 18E 23E 28E 33A 38D 43C 48D
4A 9C 14C 19C 24A 29B 34C 39B 44A 49B
5C 10A 15B 20B 25D 30B 35C 40D 45C 50E
Questions 11-12
11 An object of mass 3 kg starts from rest and
moves along the x-axis A net horizontal force
is applied to the object in +x direction The
force time relations presented by the graph
What is the net impulse delivered by this
force
(A) 6 Ns (B) 8 Ns (C) 24 Ns
(D) 30 Ns (E) 36 Ns
12 An object of mass 3 kg starts from rest and moves along the x-axis A net horizontal
force is applied to the object in +x direction The force time relations presented by the
graph What is the net work done on the object
(A) 30 J (B) 50 J (C) 90 J (D) 150 J (E) 120 J
13 A tennis ball of mass m rebounds from a vertical wall with the
same speed v as it had initially What is the change in
momentum of the ball
(A) mv (B) 2mv (C) 2mvcosθ
(D) 2mvsinθ (E) zero
14 A steel ball moving at a constant speed v on a horizontal frictionless surface collides obliquely with an identical ball initially at rest The velocity of the first ball before and after the collision is presented on the diagram What is the approximate direction of the velocity of the second ball after the collision
(A) (B) (C)
(D) (E)
Questions 15-16
15 A stationary cannon ball explodes in three pieces of masses m m and 2m The two
momenta of equal masses presented by the diagram What is the direction of the
momentum of 2m mass
(A) (B) (C) (D) (E)
16 What is the magnitude of the velocity of 2m cannon ball piece
(A) radic2
2119907 (B)
radic3
2119907 (C)
radic5
2119907 (D)
1
2119907 (E)
3
2119907
17 An object with an initial momentum shown on the diagram collides with another object at
rest Which of the following combinations of two vectors may represent the momenta of
the two objects after the collision
(A) (B) (C)
(D) (E)
Questions 18-19
A 6 kg block moves with a constant speed 5 ms on a horizontal frictionless surface and
collides elastically with an identical block initially at rest The second block collides and
sticks to the last 6 kg block initially at rest
18 What is the speed of the second 6 kg block after the first collision
(A) zero (B) 2 ms (C) 25 ms (D) 3 ms (E) 5 ms
19 What is the speed of the third 6 kg block after the second collision
(A) zero (B) 2 ms (C) 25 ms (D) 3 ms (C) 5 ms
Questions 20-21
Object A with mass 8 kg travels to the east at 10 ms and object B with mass 3 kg travels south
at 20 ms The two objects collide and stick together
20 What is the magnitude of the velocity they have after
the collision
(A) 18 ms (B) 91 ms (C) 127 ms
(D) 20 ms (E) 255 ms
21 What is the direction of the velocity they have after the
collision
(A) 30ordm south of east (B) 37ordm south of east
(C) 45ordm south of east (D) 53ordm south of east
(E) 60ordm south of east
22 Two balls of equal mass m move with equal speeds v along paths inclined at 30deg
from the horizontal as shown After the collision they stick together What is the
magnitude of their velocity
(A) radic2 v (B) 119907
2 (C)
radic2119907
2 (D)
radic3119907
2 (E) v
23 Block m1 is moving with speed vo toward stationary block m2 collides and sticks with it The speed of the center of mass of the system is
(A) 1198981
1198982119907119900 (B)
1198982+1198981
1198982119907119900 (C)
1198982+1198981
1198981119907119900 (D) (1 + 1198981)119907119900
(E) 1198981
1198981+1198982119907119900
24 A cannonball of mass 2m is moving towards the right with initial velocity vo and explodes into two equal pieces each with mass m What is the speed of the center of mass after the explosion
(A) vo (B) 05 vo (C) 2 vo (D) 4 vo (E) 0
25 A bullet of mass M1 is fired from a gun that is initially at rest The combined mass of the gun and bullet is M2 If after the bullet is fired its kinetic energy is KE what is the kinetic energy of the gun when it recoils
(A) KE (B) 1198722
1198721119870119864 (C)
11987212
11987222119870119864 (D)
1198721
1198722minus1198721119870119864 (E) radic
1198721
1198722minus1198721119870119864
26 A ball of mass m is moving to the right with speed 3v on a frictionless tabletop when it collides with a second ball of mass 3m that is moving to the right with speed v If the two balls stick together upon impact the speed of the balls immediately after the collision is
(A) v3 (B) v2 (C) 2v3 (D) 3v2 (E) 2v
27 Person A and Person B are standing on a sheet of frictionless ice Person A pushes Person B so that Person B who is 60 kg moves to the right at 3 ms while Person A who is 90 kg moves to the left at 2 ms What is the velocity of their center of mass
(A) Zero (B) 05 ms to the left (C) 1 ms to the right
(D) 24 ms to the left (E) 25 ms to the right
28 What is the rebound speed of a 4 kg ball falling straight down that hits the platform at 4 ms if the average normal force exerted by the platform on the ball was 40 N for 05s
(A) 2 ms (B) 7 ms (C) 6 ms (D) 9 ms (E) 1 ms
29 A 2 kg mass moving at 12 ms collides with an identical mass moving at -8 ms and the mass stick together What is the final velocity of the two masses
(A) 43 ms (B) 2 ms (C) 6 ms (D) 10 ms (E) 12 ms
30 A compressed spring is placed between two masses M and m resting on a smooth horizontal surface When the spring is released the two fly apart with M moving at velocity v The velocity of m is
(A) 119872
119898119907 (B) minus
119872
119898119907 (C)
119898
119872119907 (D) minus
119898
119872119907 (E)
119898
119898+119872119907
31 Consider these two cases First a car moving at 40 mph hits another car of equal mass moving at 40 mph in the opposite direction
Second a car moving at 40 mph hits a stationary steel wall
The collision time is the same for the two cases and the collisions are both inelastic In which of these cases would result in the greatest impact force
(A) Hitting the wall (B) Hitting the other car (C) The force would be the same in both cases (D) More information is needed (E)None of the above are true
Questions 32-33
A mass M moving with speed v collides with an uncompressed stationary spring of mass M with a spring constant K The surface is frictionless
32 What will be the maximum compression of the spring
(A) vradic119872119870 (B) vradic1198724119870 (C) 119907
2 radic3119872119870 (D) vradic2119872119870 (E) vradic1198722119870
33 What is the speed of the spring after the collision
(A) v (B) 119907 2frasl (C) 119907 4frasl (D) 2v (E) 119907 3frasl
Questions 34-35
A 6 kg mass is moving at 12 ms in the +x direction is acted upon by a force with magnitude given as a function of time by the graph
34 Find the magnitude of the change in momentum from time t = 0 to time t = 8 s
(A) 12 kg ms (B) 24 kg ms (C) 36 kg ms (D) 40 kg ms (E) 52 kg ms
35 What is the velocity of the mass after the force has stopped acting
(A) 6 ms (B) 10 ms (C) 18 ms (D) 24 ms (E) 40 ms
36 A wire is bent into the shape as shown above Which of the following best represents the coordinates of the center of mass
(A) (1314 67) (B) (87 67) (C) (1314 87) (D) (11) (E) (167)
37 A block of mass m is moving with speed vo to the right on a frictionless surface when it explodes into two pieces of unequal mass One piece of the mass 3m4 moves with a speed vo2 to the left while the other piece of the object moves with velocity
(A) vo2 (B) 2vo3 (C) 11vo2 (D) 7vo5 (E) 2vo
38 Two blocks with masses m and 2m are placed on a horizontal frictionless surface There is a compressed spring between the block and after the spring is released 2m block moves to the right with a speed of v What is the total work done by the spring on the system of two blocks
(A) Zero (B) mv2 (C) 2mv2 (D) 3mv2 (E) mv
39 A railway artillery gun of mass 1400 tonnes is initially at rest on a horizontal surface when fires a 7 tonnes shell with a velocity of 800 ms at an angle of 60deg What is the speed of the gun immediately after the shell is fired
(A) Zero (B) 2 ms (C) 4 ms (D) 5 ms (E) 7 ms
40 Two equal forces are exerted for the same length of time on two blocks with different masses m1 and m2 (m2 gtm1) Which of the following will describe the change is kinetic energy of the blocks
(A) Blocks have the same change in kinetic energy
(B) The change in kinetic energy of each block is zero
(C) Block m2 has greater change in kinetic energy
(D) Block m1 has greater change in kinetic energy
(E) Non from the above is correct
41 A boy launches a 20 g dart in horizontal by a spring gun from a balcony 45 m above the ground The dart lands 15 m away from the balcony If the length of the gunrsquos barrel is 10 cm what is the average horizontal force applied by the spring
(A) 10 N (B) 20 N (C) 25 N (D) 50 N (E) 75 N
42 A mall of mass m is dropped from a height of ho The ball hits the floor and bounces to a height of h What is the magnitude of impulse exerted on the ball by the floor
(A) mgh (B) 2mgh (C) radic2119898119892ℎ (D) 119898radic2119892(ℎ minus ℎ119900) (E) 119898radic2119892(ℎ + ℎ119900)
43 A 5 kg object starts from rest on a flat horizontal surface and moves in a straight line The velocity as a function of time is given by v = 3t + 2t2 What is the magnitude of instantaneous force that acts on the object at 2 s
(A) 105 N (B) 75 N (C) 55 N (D) 45 N (E) 35 N
44 A net force F = 10 + 6t2 is applied to a 30 kg cart that can move on a flat horizontal surface If the cart starts from rest what is its speed at 5 s
(A) 10 ms (B) 8 ms (C) 5 ms (D) 3 ms (E) 1 ms
45 Block of mass m moves to the right at a constant velocity v and collides elastically with another block of mass 3m Which of the following is the velocity of each block after the collision
Block m Block 3m
(A) Zero v
(B) v2 v2
(C) ndashv2 v2
(D) 3v2 v2
(E) ndashv2 3v2
46 A 40 kg skateboarder runs at a constant velocity of 12 ms and jumps of a
stationary skateboard with a mass of 8 kg What is the velocity of the
skateboard after the jump
(A) 12 ms (B) 90 ms (C) 60 ms (D) 20 ms (E) 10 ms
47 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves
at a constant velocity of 2 ms What is the velocity of the boat after the jump if the
diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the
boat
(A) 2 ms (B) 3 ms (C) 4 ms (D) 5 ms (E) 6 ms
48 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back
with a momentum of 6 kgms after the collision with the racket What is the change
in momentum of the tennis ball
(A) 1 kgms (B) 5 kgms (C) 6 kgms (D) 11 kgms 0 kgms
49 A light beach ball moving with a velocity 2 ms to the right collides elastically with a
stationary bowling ball After the collision the bowling ball remains stationary What is
the velocity of the beach ball after the collision
(A) 0 ms (B) 2 ms to the left (C) 4 ms to the left
(D) 3 ms to the left (E) 1 ms to the left
50 A of mass m moving at a constant speed v to the right collides elastically with
another ball of mass 3m moving to the left at a constant speed v What is the velocity
of ball m after the collision
(A) v (B) minus3
2v (C) minus
1
3v (D) 2v (E) -2v
Answer Key
1A 6B 11D 16A 21B 26D 31C 36A 41C 46E
2A 7A 12D 17E 22D 27A 32E 37C 42E 47B
3B 8D 13C 18E 23E 28E 33A 38D 43C 48D
4A 9C 14C 19C 24A 29B 34C 39B 44A 49B
5C 10A 15B 20B 25D 30B 35C 40D 45C 50E
14 A steel ball moving at a constant speed v on a horizontal frictionless surface collides obliquely with an identical ball initially at rest The velocity of the first ball before and after the collision is presented on the diagram What is the approximate direction of the velocity of the second ball after the collision
(A) (B) (C)
(D) (E)
Questions 15-16
15 A stationary cannon ball explodes in three pieces of masses m m and 2m The two
momenta of equal masses presented by the diagram What is the direction of the
momentum of 2m mass
(A) (B) (C) (D) (E)
16 What is the magnitude of the velocity of 2m cannon ball piece
(A) radic2
2119907 (B)
radic3
2119907 (C)
radic5
2119907 (D)
1
2119907 (E)
3
2119907
17 An object with an initial momentum shown on the diagram collides with another object at
rest Which of the following combinations of two vectors may represent the momenta of
the two objects after the collision
(A) (B) (C)
(D) (E)
Questions 18-19
A 6 kg block moves with a constant speed 5 ms on a horizontal frictionless surface and
collides elastically with an identical block initially at rest The second block collides and
sticks to the last 6 kg block initially at rest
18 What is the speed of the second 6 kg block after the first collision
(A) zero (B) 2 ms (C) 25 ms (D) 3 ms (E) 5 ms
19 What is the speed of the third 6 kg block after the second collision
(A) zero (B) 2 ms (C) 25 ms (D) 3 ms (C) 5 ms
Questions 20-21
Object A with mass 8 kg travels to the east at 10 ms and object B with mass 3 kg travels south
at 20 ms The two objects collide and stick together
20 What is the magnitude of the velocity they have after
the collision
(A) 18 ms (B) 91 ms (C) 127 ms
(D) 20 ms (E) 255 ms
21 What is the direction of the velocity they have after the
collision
(A) 30ordm south of east (B) 37ordm south of east
(C) 45ordm south of east (D) 53ordm south of east
(E) 60ordm south of east
22 Two balls of equal mass m move with equal speeds v along paths inclined at 30deg
from the horizontal as shown After the collision they stick together What is the
magnitude of their velocity
(A) radic2 v (B) 119907
2 (C)
radic2119907
2 (D)
radic3119907
2 (E) v
23 Block m1 is moving with speed vo toward stationary block m2 collides and sticks with it The speed of the center of mass of the system is
(A) 1198981
1198982119907119900 (B)
1198982+1198981
1198982119907119900 (C)
1198982+1198981
1198981119907119900 (D) (1 + 1198981)119907119900
(E) 1198981
1198981+1198982119907119900
24 A cannonball of mass 2m is moving towards the right with initial velocity vo and explodes into two equal pieces each with mass m What is the speed of the center of mass after the explosion
(A) vo (B) 05 vo (C) 2 vo (D) 4 vo (E) 0
25 A bullet of mass M1 is fired from a gun that is initially at rest The combined mass of the gun and bullet is M2 If after the bullet is fired its kinetic energy is KE what is the kinetic energy of the gun when it recoils
(A) KE (B) 1198722
1198721119870119864 (C)
11987212
11987222119870119864 (D)
1198721
1198722minus1198721119870119864 (E) radic
1198721
1198722minus1198721119870119864
26 A ball of mass m is moving to the right with speed 3v on a frictionless tabletop when it collides with a second ball of mass 3m that is moving to the right with speed v If the two balls stick together upon impact the speed of the balls immediately after the collision is
(A) v3 (B) v2 (C) 2v3 (D) 3v2 (E) 2v
27 Person A and Person B are standing on a sheet of frictionless ice Person A pushes Person B so that Person B who is 60 kg moves to the right at 3 ms while Person A who is 90 kg moves to the left at 2 ms What is the velocity of their center of mass
(A) Zero (B) 05 ms to the left (C) 1 ms to the right
(D) 24 ms to the left (E) 25 ms to the right
28 What is the rebound speed of a 4 kg ball falling straight down that hits the platform at 4 ms if the average normal force exerted by the platform on the ball was 40 N for 05s
(A) 2 ms (B) 7 ms (C) 6 ms (D) 9 ms (E) 1 ms
29 A 2 kg mass moving at 12 ms collides with an identical mass moving at -8 ms and the mass stick together What is the final velocity of the two masses
(A) 43 ms (B) 2 ms (C) 6 ms (D) 10 ms (E) 12 ms
30 A compressed spring is placed between two masses M and m resting on a smooth horizontal surface When the spring is released the two fly apart with M moving at velocity v The velocity of m is
(A) 119872
119898119907 (B) minus
119872
119898119907 (C)
119898
119872119907 (D) minus
119898
119872119907 (E)
119898
119898+119872119907
31 Consider these two cases First a car moving at 40 mph hits another car of equal mass moving at 40 mph in the opposite direction
Second a car moving at 40 mph hits a stationary steel wall
The collision time is the same for the two cases and the collisions are both inelastic In which of these cases would result in the greatest impact force
(A) Hitting the wall (B) Hitting the other car (C) The force would be the same in both cases (D) More information is needed (E)None of the above are true
Questions 32-33
A mass M moving with speed v collides with an uncompressed stationary spring of mass M with a spring constant K The surface is frictionless
32 What will be the maximum compression of the spring
(A) vradic119872119870 (B) vradic1198724119870 (C) 119907
2 radic3119872119870 (D) vradic2119872119870 (E) vradic1198722119870
33 What is the speed of the spring after the collision
(A) v (B) 119907 2frasl (C) 119907 4frasl (D) 2v (E) 119907 3frasl
Questions 34-35
A 6 kg mass is moving at 12 ms in the +x direction is acted upon by a force with magnitude given as a function of time by the graph
34 Find the magnitude of the change in momentum from time t = 0 to time t = 8 s
(A) 12 kg ms (B) 24 kg ms (C) 36 kg ms (D) 40 kg ms (E) 52 kg ms
35 What is the velocity of the mass after the force has stopped acting
(A) 6 ms (B) 10 ms (C) 18 ms (D) 24 ms (E) 40 ms
36 A wire is bent into the shape as shown above Which of the following best represents the coordinates of the center of mass
(A) (1314 67) (B) (87 67) (C) (1314 87) (D) (11) (E) (167)
37 A block of mass m is moving with speed vo to the right on a frictionless surface when it explodes into two pieces of unequal mass One piece of the mass 3m4 moves with a speed vo2 to the left while the other piece of the object moves with velocity
(A) vo2 (B) 2vo3 (C) 11vo2 (D) 7vo5 (E) 2vo
38 Two blocks with masses m and 2m are placed on a horizontal frictionless surface There is a compressed spring between the block and after the spring is released 2m block moves to the right with a speed of v What is the total work done by the spring on the system of two blocks
(A) Zero (B) mv2 (C) 2mv2 (D) 3mv2 (E) mv
39 A railway artillery gun of mass 1400 tonnes is initially at rest on a horizontal surface when fires a 7 tonnes shell with a velocity of 800 ms at an angle of 60deg What is the speed of the gun immediately after the shell is fired
(A) Zero (B) 2 ms (C) 4 ms (D) 5 ms (E) 7 ms
40 Two equal forces are exerted for the same length of time on two blocks with different masses m1 and m2 (m2 gtm1) Which of the following will describe the change is kinetic energy of the blocks
(A) Blocks have the same change in kinetic energy
(B) The change in kinetic energy of each block is zero
(C) Block m2 has greater change in kinetic energy
(D) Block m1 has greater change in kinetic energy
(E) Non from the above is correct
41 A boy launches a 20 g dart in horizontal by a spring gun from a balcony 45 m above the ground The dart lands 15 m away from the balcony If the length of the gunrsquos barrel is 10 cm what is the average horizontal force applied by the spring
(A) 10 N (B) 20 N (C) 25 N (D) 50 N (E) 75 N
42 A mall of mass m is dropped from a height of ho The ball hits the floor and bounces to a height of h What is the magnitude of impulse exerted on the ball by the floor
(A) mgh (B) 2mgh (C) radic2119898119892ℎ (D) 119898radic2119892(ℎ minus ℎ119900) (E) 119898radic2119892(ℎ + ℎ119900)
43 A 5 kg object starts from rest on a flat horizontal surface and moves in a straight line The velocity as a function of time is given by v = 3t + 2t2 What is the magnitude of instantaneous force that acts on the object at 2 s
(A) 105 N (B) 75 N (C) 55 N (D) 45 N (E) 35 N
44 A net force F = 10 + 6t2 is applied to a 30 kg cart that can move on a flat horizontal surface If the cart starts from rest what is its speed at 5 s
(A) 10 ms (B) 8 ms (C) 5 ms (D) 3 ms (E) 1 ms
45 Block of mass m moves to the right at a constant velocity v and collides elastically with another block of mass 3m Which of the following is the velocity of each block after the collision
Block m Block 3m
(A) Zero v
(B) v2 v2
(C) ndashv2 v2
(D) 3v2 v2
(E) ndashv2 3v2
46 A 40 kg skateboarder runs at a constant velocity of 12 ms and jumps of a
stationary skateboard with a mass of 8 kg What is the velocity of the
skateboard after the jump
(A) 12 ms (B) 90 ms (C) 60 ms (D) 20 ms (E) 10 ms
47 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves
at a constant velocity of 2 ms What is the velocity of the boat after the jump if the
diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the
boat
(A) 2 ms (B) 3 ms (C) 4 ms (D) 5 ms (E) 6 ms
48 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back
with a momentum of 6 kgms after the collision with the racket What is the change
in momentum of the tennis ball
(A) 1 kgms (B) 5 kgms (C) 6 kgms (D) 11 kgms 0 kgms
49 A light beach ball moving with a velocity 2 ms to the right collides elastically with a
stationary bowling ball After the collision the bowling ball remains stationary What is
the velocity of the beach ball after the collision
(A) 0 ms (B) 2 ms to the left (C) 4 ms to the left
(D) 3 ms to the left (E) 1 ms to the left
50 A of mass m moving at a constant speed v to the right collides elastically with
another ball of mass 3m moving to the left at a constant speed v What is the velocity
of ball m after the collision
(A) v (B) minus3
2v (C) minus
1
3v (D) 2v (E) -2v
Answer Key
1A 6B 11D 16A 21B 26D 31C 36A 41C 46E
2A 7A 12D 17E 22D 27A 32E 37C 42E 47B
3B 8D 13C 18E 23E 28E 33A 38D 43C 48D
4A 9C 14C 19C 24A 29B 34C 39B 44A 49B
5C 10A 15B 20B 25D 30B 35C 40D 45C 50E
17 An object with an initial momentum shown on the diagram collides with another object at
rest Which of the following combinations of two vectors may represent the momenta of
the two objects after the collision
(A) (B) (C)
(D) (E)
Questions 18-19
A 6 kg block moves with a constant speed 5 ms on a horizontal frictionless surface and
collides elastically with an identical block initially at rest The second block collides and
sticks to the last 6 kg block initially at rest
18 What is the speed of the second 6 kg block after the first collision
(A) zero (B) 2 ms (C) 25 ms (D) 3 ms (E) 5 ms
19 What is the speed of the third 6 kg block after the second collision
(A) zero (B) 2 ms (C) 25 ms (D) 3 ms (C) 5 ms
Questions 20-21
Object A with mass 8 kg travels to the east at 10 ms and object B with mass 3 kg travels south
at 20 ms The two objects collide and stick together
20 What is the magnitude of the velocity they have after
the collision
(A) 18 ms (B) 91 ms (C) 127 ms
(D) 20 ms (E) 255 ms
21 What is the direction of the velocity they have after the
collision
(A) 30ordm south of east (B) 37ordm south of east
(C) 45ordm south of east (D) 53ordm south of east
(E) 60ordm south of east
22 Two balls of equal mass m move with equal speeds v along paths inclined at 30deg
from the horizontal as shown After the collision they stick together What is the
magnitude of their velocity
(A) radic2 v (B) 119907
2 (C)
radic2119907
2 (D)
radic3119907
2 (E) v
23 Block m1 is moving with speed vo toward stationary block m2 collides and sticks with it The speed of the center of mass of the system is
(A) 1198981
1198982119907119900 (B)
1198982+1198981
1198982119907119900 (C)
1198982+1198981
1198981119907119900 (D) (1 + 1198981)119907119900
(E) 1198981
1198981+1198982119907119900
24 A cannonball of mass 2m is moving towards the right with initial velocity vo and explodes into two equal pieces each with mass m What is the speed of the center of mass after the explosion
(A) vo (B) 05 vo (C) 2 vo (D) 4 vo (E) 0
25 A bullet of mass M1 is fired from a gun that is initially at rest The combined mass of the gun and bullet is M2 If after the bullet is fired its kinetic energy is KE what is the kinetic energy of the gun when it recoils
(A) KE (B) 1198722
1198721119870119864 (C)
11987212
11987222119870119864 (D)
1198721
1198722minus1198721119870119864 (E) radic
1198721
1198722minus1198721119870119864
26 A ball of mass m is moving to the right with speed 3v on a frictionless tabletop when it collides with a second ball of mass 3m that is moving to the right with speed v If the two balls stick together upon impact the speed of the balls immediately after the collision is
(A) v3 (B) v2 (C) 2v3 (D) 3v2 (E) 2v
27 Person A and Person B are standing on a sheet of frictionless ice Person A pushes Person B so that Person B who is 60 kg moves to the right at 3 ms while Person A who is 90 kg moves to the left at 2 ms What is the velocity of their center of mass
(A) Zero (B) 05 ms to the left (C) 1 ms to the right
(D) 24 ms to the left (E) 25 ms to the right
28 What is the rebound speed of a 4 kg ball falling straight down that hits the platform at 4 ms if the average normal force exerted by the platform on the ball was 40 N for 05s
(A) 2 ms (B) 7 ms (C) 6 ms (D) 9 ms (E) 1 ms
29 A 2 kg mass moving at 12 ms collides with an identical mass moving at -8 ms and the mass stick together What is the final velocity of the two masses
(A) 43 ms (B) 2 ms (C) 6 ms (D) 10 ms (E) 12 ms
30 A compressed spring is placed between two masses M and m resting on a smooth horizontal surface When the spring is released the two fly apart with M moving at velocity v The velocity of m is
(A) 119872
119898119907 (B) minus
119872
119898119907 (C)
119898
119872119907 (D) minus
119898
119872119907 (E)
119898
119898+119872119907
31 Consider these two cases First a car moving at 40 mph hits another car of equal mass moving at 40 mph in the opposite direction
Second a car moving at 40 mph hits a stationary steel wall
The collision time is the same for the two cases and the collisions are both inelastic In which of these cases would result in the greatest impact force
(A) Hitting the wall (B) Hitting the other car (C) The force would be the same in both cases (D) More information is needed (E)None of the above are true
Questions 32-33
A mass M moving with speed v collides with an uncompressed stationary spring of mass M with a spring constant K The surface is frictionless
32 What will be the maximum compression of the spring
(A) vradic119872119870 (B) vradic1198724119870 (C) 119907
2 radic3119872119870 (D) vradic2119872119870 (E) vradic1198722119870
33 What is the speed of the spring after the collision
(A) v (B) 119907 2frasl (C) 119907 4frasl (D) 2v (E) 119907 3frasl
Questions 34-35
A 6 kg mass is moving at 12 ms in the +x direction is acted upon by a force with magnitude given as a function of time by the graph
34 Find the magnitude of the change in momentum from time t = 0 to time t = 8 s
(A) 12 kg ms (B) 24 kg ms (C) 36 kg ms (D) 40 kg ms (E) 52 kg ms
35 What is the velocity of the mass after the force has stopped acting
(A) 6 ms (B) 10 ms (C) 18 ms (D) 24 ms (E) 40 ms
36 A wire is bent into the shape as shown above Which of the following best represents the coordinates of the center of mass
(A) (1314 67) (B) (87 67) (C) (1314 87) (D) (11) (E) (167)
37 A block of mass m is moving with speed vo to the right on a frictionless surface when it explodes into two pieces of unequal mass One piece of the mass 3m4 moves with a speed vo2 to the left while the other piece of the object moves with velocity
(A) vo2 (B) 2vo3 (C) 11vo2 (D) 7vo5 (E) 2vo
38 Two blocks with masses m and 2m are placed on a horizontal frictionless surface There is a compressed spring between the block and after the spring is released 2m block moves to the right with a speed of v What is the total work done by the spring on the system of two blocks
(A) Zero (B) mv2 (C) 2mv2 (D) 3mv2 (E) mv
39 A railway artillery gun of mass 1400 tonnes is initially at rest on a horizontal surface when fires a 7 tonnes shell with a velocity of 800 ms at an angle of 60deg What is the speed of the gun immediately after the shell is fired
(A) Zero (B) 2 ms (C) 4 ms (D) 5 ms (E) 7 ms
40 Two equal forces are exerted for the same length of time on two blocks with different masses m1 and m2 (m2 gtm1) Which of the following will describe the change is kinetic energy of the blocks
(A) Blocks have the same change in kinetic energy
(B) The change in kinetic energy of each block is zero
(C) Block m2 has greater change in kinetic energy
(D) Block m1 has greater change in kinetic energy
(E) Non from the above is correct
41 A boy launches a 20 g dart in horizontal by a spring gun from a balcony 45 m above the ground The dart lands 15 m away from the balcony If the length of the gunrsquos barrel is 10 cm what is the average horizontal force applied by the spring
(A) 10 N (B) 20 N (C) 25 N (D) 50 N (E) 75 N
42 A mall of mass m is dropped from a height of ho The ball hits the floor and bounces to a height of h What is the magnitude of impulse exerted on the ball by the floor
(A) mgh (B) 2mgh (C) radic2119898119892ℎ (D) 119898radic2119892(ℎ minus ℎ119900) (E) 119898radic2119892(ℎ + ℎ119900)
43 A 5 kg object starts from rest on a flat horizontal surface and moves in a straight line The velocity as a function of time is given by v = 3t + 2t2 What is the magnitude of instantaneous force that acts on the object at 2 s
(A) 105 N (B) 75 N (C) 55 N (D) 45 N (E) 35 N
44 A net force F = 10 + 6t2 is applied to a 30 kg cart that can move on a flat horizontal surface If the cart starts from rest what is its speed at 5 s
(A) 10 ms (B) 8 ms (C) 5 ms (D) 3 ms (E) 1 ms
45 Block of mass m moves to the right at a constant velocity v and collides elastically with another block of mass 3m Which of the following is the velocity of each block after the collision
Block m Block 3m
(A) Zero v
(B) v2 v2
(C) ndashv2 v2
(D) 3v2 v2
(E) ndashv2 3v2
46 A 40 kg skateboarder runs at a constant velocity of 12 ms and jumps of a
stationary skateboard with a mass of 8 kg What is the velocity of the
skateboard after the jump
(A) 12 ms (B) 90 ms (C) 60 ms (D) 20 ms (E) 10 ms
47 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves
at a constant velocity of 2 ms What is the velocity of the boat after the jump if the
diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the
boat
(A) 2 ms (B) 3 ms (C) 4 ms (D) 5 ms (E) 6 ms
48 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back
with a momentum of 6 kgms after the collision with the racket What is the change
in momentum of the tennis ball
(A) 1 kgms (B) 5 kgms (C) 6 kgms (D) 11 kgms 0 kgms
49 A light beach ball moving with a velocity 2 ms to the right collides elastically with a
stationary bowling ball After the collision the bowling ball remains stationary What is
the velocity of the beach ball after the collision
(A) 0 ms (B) 2 ms to the left (C) 4 ms to the left
(D) 3 ms to the left (E) 1 ms to the left
50 A of mass m moving at a constant speed v to the right collides elastically with
another ball of mass 3m moving to the left at a constant speed v What is the velocity
of ball m after the collision
(A) v (B) minus3
2v (C) minus
1
3v (D) 2v (E) -2v
Answer Key
1A 6B 11D 16A 21B 26D 31C 36A 41C 46E
2A 7A 12D 17E 22D 27A 32E 37C 42E 47B
3B 8D 13C 18E 23E 28E 33A 38D 43C 48D
4A 9C 14C 19C 24A 29B 34C 39B 44A 49B
5C 10A 15B 20B 25D 30B 35C 40D 45C 50E
Questions 20-21
Object A with mass 8 kg travels to the east at 10 ms and object B with mass 3 kg travels south
at 20 ms The two objects collide and stick together
20 What is the magnitude of the velocity they have after
the collision
(A) 18 ms (B) 91 ms (C) 127 ms
(D) 20 ms (E) 255 ms
21 What is the direction of the velocity they have after the
collision
(A) 30ordm south of east (B) 37ordm south of east
(C) 45ordm south of east (D) 53ordm south of east
(E) 60ordm south of east
22 Two balls of equal mass m move with equal speeds v along paths inclined at 30deg
from the horizontal as shown After the collision they stick together What is the
magnitude of their velocity
(A) radic2 v (B) 119907
2 (C)
radic2119907
2 (D)
radic3119907
2 (E) v
23 Block m1 is moving with speed vo toward stationary block m2 collides and sticks with it The speed of the center of mass of the system is
(A) 1198981
1198982119907119900 (B)
1198982+1198981
1198982119907119900 (C)
1198982+1198981
1198981119907119900 (D) (1 + 1198981)119907119900
(E) 1198981
1198981+1198982119907119900
24 A cannonball of mass 2m is moving towards the right with initial velocity vo and explodes into two equal pieces each with mass m What is the speed of the center of mass after the explosion
(A) vo (B) 05 vo (C) 2 vo (D) 4 vo (E) 0
25 A bullet of mass M1 is fired from a gun that is initially at rest The combined mass of the gun and bullet is M2 If after the bullet is fired its kinetic energy is KE what is the kinetic energy of the gun when it recoils
(A) KE (B) 1198722
1198721119870119864 (C)
11987212
11987222119870119864 (D)
1198721
1198722minus1198721119870119864 (E) radic
1198721
1198722minus1198721119870119864
26 A ball of mass m is moving to the right with speed 3v on a frictionless tabletop when it collides with a second ball of mass 3m that is moving to the right with speed v If the two balls stick together upon impact the speed of the balls immediately after the collision is
(A) v3 (B) v2 (C) 2v3 (D) 3v2 (E) 2v
27 Person A and Person B are standing on a sheet of frictionless ice Person A pushes Person B so that Person B who is 60 kg moves to the right at 3 ms while Person A who is 90 kg moves to the left at 2 ms What is the velocity of their center of mass
(A) Zero (B) 05 ms to the left (C) 1 ms to the right
(D) 24 ms to the left (E) 25 ms to the right
28 What is the rebound speed of a 4 kg ball falling straight down that hits the platform at 4 ms if the average normal force exerted by the platform on the ball was 40 N for 05s
(A) 2 ms (B) 7 ms (C) 6 ms (D) 9 ms (E) 1 ms
29 A 2 kg mass moving at 12 ms collides with an identical mass moving at -8 ms and the mass stick together What is the final velocity of the two masses
(A) 43 ms (B) 2 ms (C) 6 ms (D) 10 ms (E) 12 ms
30 A compressed spring is placed between two masses M and m resting on a smooth horizontal surface When the spring is released the two fly apart with M moving at velocity v The velocity of m is
(A) 119872
119898119907 (B) minus
119872
119898119907 (C)
119898
119872119907 (D) minus
119898
119872119907 (E)
119898
119898+119872119907
31 Consider these two cases First a car moving at 40 mph hits another car of equal mass moving at 40 mph in the opposite direction
Second a car moving at 40 mph hits a stationary steel wall
The collision time is the same for the two cases and the collisions are both inelastic In which of these cases would result in the greatest impact force
(A) Hitting the wall (B) Hitting the other car (C) The force would be the same in both cases (D) More information is needed (E)None of the above are true
Questions 32-33
A mass M moving with speed v collides with an uncompressed stationary spring of mass M with a spring constant K The surface is frictionless
32 What will be the maximum compression of the spring
(A) vradic119872119870 (B) vradic1198724119870 (C) 119907
2 radic3119872119870 (D) vradic2119872119870 (E) vradic1198722119870
33 What is the speed of the spring after the collision
(A) v (B) 119907 2frasl (C) 119907 4frasl (D) 2v (E) 119907 3frasl
Questions 34-35
A 6 kg mass is moving at 12 ms in the +x direction is acted upon by a force with magnitude given as a function of time by the graph
34 Find the magnitude of the change in momentum from time t = 0 to time t = 8 s
(A) 12 kg ms (B) 24 kg ms (C) 36 kg ms (D) 40 kg ms (E) 52 kg ms
35 What is the velocity of the mass after the force has stopped acting
(A) 6 ms (B) 10 ms (C) 18 ms (D) 24 ms (E) 40 ms
36 A wire is bent into the shape as shown above Which of the following best represents the coordinates of the center of mass
(A) (1314 67) (B) (87 67) (C) (1314 87) (D) (11) (E) (167)
37 A block of mass m is moving with speed vo to the right on a frictionless surface when it explodes into two pieces of unequal mass One piece of the mass 3m4 moves with a speed vo2 to the left while the other piece of the object moves with velocity
(A) vo2 (B) 2vo3 (C) 11vo2 (D) 7vo5 (E) 2vo
38 Two blocks with masses m and 2m are placed on a horizontal frictionless surface There is a compressed spring between the block and after the spring is released 2m block moves to the right with a speed of v What is the total work done by the spring on the system of two blocks
(A) Zero (B) mv2 (C) 2mv2 (D) 3mv2 (E) mv
39 A railway artillery gun of mass 1400 tonnes is initially at rest on a horizontal surface when fires a 7 tonnes shell with a velocity of 800 ms at an angle of 60deg What is the speed of the gun immediately after the shell is fired
(A) Zero (B) 2 ms (C) 4 ms (D) 5 ms (E) 7 ms
40 Two equal forces are exerted for the same length of time on two blocks with different masses m1 and m2 (m2 gtm1) Which of the following will describe the change is kinetic energy of the blocks
(A) Blocks have the same change in kinetic energy
(B) The change in kinetic energy of each block is zero
(C) Block m2 has greater change in kinetic energy
(D) Block m1 has greater change in kinetic energy
(E) Non from the above is correct
41 A boy launches a 20 g dart in horizontal by a spring gun from a balcony 45 m above the ground The dart lands 15 m away from the balcony If the length of the gunrsquos barrel is 10 cm what is the average horizontal force applied by the spring
(A) 10 N (B) 20 N (C) 25 N (D) 50 N (E) 75 N
42 A mall of mass m is dropped from a height of ho The ball hits the floor and bounces to a height of h What is the magnitude of impulse exerted on the ball by the floor
(A) mgh (B) 2mgh (C) radic2119898119892ℎ (D) 119898radic2119892(ℎ minus ℎ119900) (E) 119898radic2119892(ℎ + ℎ119900)
43 A 5 kg object starts from rest on a flat horizontal surface and moves in a straight line The velocity as a function of time is given by v = 3t + 2t2 What is the magnitude of instantaneous force that acts on the object at 2 s
(A) 105 N (B) 75 N (C) 55 N (D) 45 N (E) 35 N
44 A net force F = 10 + 6t2 is applied to a 30 kg cart that can move on a flat horizontal surface If the cart starts from rest what is its speed at 5 s
(A) 10 ms (B) 8 ms (C) 5 ms (D) 3 ms (E) 1 ms
45 Block of mass m moves to the right at a constant velocity v and collides elastically with another block of mass 3m Which of the following is the velocity of each block after the collision
Block m Block 3m
(A) Zero v
(B) v2 v2
(C) ndashv2 v2
(D) 3v2 v2
(E) ndashv2 3v2
46 A 40 kg skateboarder runs at a constant velocity of 12 ms and jumps of a
stationary skateboard with a mass of 8 kg What is the velocity of the
skateboard after the jump
(A) 12 ms (B) 90 ms (C) 60 ms (D) 20 ms (E) 10 ms
47 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves
at a constant velocity of 2 ms What is the velocity of the boat after the jump if the
diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the
boat
(A) 2 ms (B) 3 ms (C) 4 ms (D) 5 ms (E) 6 ms
48 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back
with a momentum of 6 kgms after the collision with the racket What is the change
in momentum of the tennis ball
(A) 1 kgms (B) 5 kgms (C) 6 kgms (D) 11 kgms 0 kgms
49 A light beach ball moving with a velocity 2 ms to the right collides elastically with a
stationary bowling ball After the collision the bowling ball remains stationary What is
the velocity of the beach ball after the collision
(A) 0 ms (B) 2 ms to the left (C) 4 ms to the left
(D) 3 ms to the left (E) 1 ms to the left
50 A of mass m moving at a constant speed v to the right collides elastically with
another ball of mass 3m moving to the left at a constant speed v What is the velocity
of ball m after the collision
(A) v (B) minus3
2v (C) minus
1
3v (D) 2v (E) -2v
Answer Key
1A 6B 11D 16A 21B 26D 31C 36A 41C 46E
2A 7A 12D 17E 22D 27A 32E 37C 42E 47B
3B 8D 13C 18E 23E 28E 33A 38D 43C 48D
4A 9C 14C 19C 24A 29B 34C 39B 44A 49B
5C 10A 15B 20B 25D 30B 35C 40D 45C 50E
25 A bullet of mass M1 is fired from a gun that is initially at rest The combined mass of the gun and bullet is M2 If after the bullet is fired its kinetic energy is KE what is the kinetic energy of the gun when it recoils
(A) KE (B) 1198722
1198721119870119864 (C)
11987212
11987222119870119864 (D)
1198721
1198722minus1198721119870119864 (E) radic
1198721
1198722minus1198721119870119864
26 A ball of mass m is moving to the right with speed 3v on a frictionless tabletop when it collides with a second ball of mass 3m that is moving to the right with speed v If the two balls stick together upon impact the speed of the balls immediately after the collision is
(A) v3 (B) v2 (C) 2v3 (D) 3v2 (E) 2v
27 Person A and Person B are standing on a sheet of frictionless ice Person A pushes Person B so that Person B who is 60 kg moves to the right at 3 ms while Person A who is 90 kg moves to the left at 2 ms What is the velocity of their center of mass
(A) Zero (B) 05 ms to the left (C) 1 ms to the right
(D) 24 ms to the left (E) 25 ms to the right
28 What is the rebound speed of a 4 kg ball falling straight down that hits the platform at 4 ms if the average normal force exerted by the platform on the ball was 40 N for 05s
(A) 2 ms (B) 7 ms (C) 6 ms (D) 9 ms (E) 1 ms
29 A 2 kg mass moving at 12 ms collides with an identical mass moving at -8 ms and the mass stick together What is the final velocity of the two masses
(A) 43 ms (B) 2 ms (C) 6 ms (D) 10 ms (E) 12 ms
30 A compressed spring is placed between two masses M and m resting on a smooth horizontal surface When the spring is released the two fly apart with M moving at velocity v The velocity of m is
(A) 119872
119898119907 (B) minus
119872
119898119907 (C)
119898
119872119907 (D) minus
119898
119872119907 (E)
119898
119898+119872119907
31 Consider these two cases First a car moving at 40 mph hits another car of equal mass moving at 40 mph in the opposite direction
Second a car moving at 40 mph hits a stationary steel wall
The collision time is the same for the two cases and the collisions are both inelastic In which of these cases would result in the greatest impact force
(A) Hitting the wall (B) Hitting the other car (C) The force would be the same in both cases (D) More information is needed (E)None of the above are true
Questions 32-33
A mass M moving with speed v collides with an uncompressed stationary spring of mass M with a spring constant K The surface is frictionless
32 What will be the maximum compression of the spring
(A) vradic119872119870 (B) vradic1198724119870 (C) 119907
2 radic3119872119870 (D) vradic2119872119870 (E) vradic1198722119870
33 What is the speed of the spring after the collision
(A) v (B) 119907 2frasl (C) 119907 4frasl (D) 2v (E) 119907 3frasl
Questions 34-35
A 6 kg mass is moving at 12 ms in the +x direction is acted upon by a force with magnitude given as a function of time by the graph
34 Find the magnitude of the change in momentum from time t = 0 to time t = 8 s
(A) 12 kg ms (B) 24 kg ms (C) 36 kg ms (D) 40 kg ms (E) 52 kg ms
35 What is the velocity of the mass after the force has stopped acting
(A) 6 ms (B) 10 ms (C) 18 ms (D) 24 ms (E) 40 ms
36 A wire is bent into the shape as shown above Which of the following best represents the coordinates of the center of mass
(A) (1314 67) (B) (87 67) (C) (1314 87) (D) (11) (E) (167)
37 A block of mass m is moving with speed vo to the right on a frictionless surface when it explodes into two pieces of unequal mass One piece of the mass 3m4 moves with a speed vo2 to the left while the other piece of the object moves with velocity
(A) vo2 (B) 2vo3 (C) 11vo2 (D) 7vo5 (E) 2vo
38 Two blocks with masses m and 2m are placed on a horizontal frictionless surface There is a compressed spring between the block and after the spring is released 2m block moves to the right with a speed of v What is the total work done by the spring on the system of two blocks
(A) Zero (B) mv2 (C) 2mv2 (D) 3mv2 (E) mv
39 A railway artillery gun of mass 1400 tonnes is initially at rest on a horizontal surface when fires a 7 tonnes shell with a velocity of 800 ms at an angle of 60deg What is the speed of the gun immediately after the shell is fired
(A) Zero (B) 2 ms (C) 4 ms (D) 5 ms (E) 7 ms
40 Two equal forces are exerted for the same length of time on two blocks with different masses m1 and m2 (m2 gtm1) Which of the following will describe the change is kinetic energy of the blocks
(A) Blocks have the same change in kinetic energy
(B) The change in kinetic energy of each block is zero
(C) Block m2 has greater change in kinetic energy
(D) Block m1 has greater change in kinetic energy
(E) Non from the above is correct
41 A boy launches a 20 g dart in horizontal by a spring gun from a balcony 45 m above the ground The dart lands 15 m away from the balcony If the length of the gunrsquos barrel is 10 cm what is the average horizontal force applied by the spring
(A) 10 N (B) 20 N (C) 25 N (D) 50 N (E) 75 N
42 A mall of mass m is dropped from a height of ho The ball hits the floor and bounces to a height of h What is the magnitude of impulse exerted on the ball by the floor
(A) mgh (B) 2mgh (C) radic2119898119892ℎ (D) 119898radic2119892(ℎ minus ℎ119900) (E) 119898radic2119892(ℎ + ℎ119900)
43 A 5 kg object starts from rest on a flat horizontal surface and moves in a straight line The velocity as a function of time is given by v = 3t + 2t2 What is the magnitude of instantaneous force that acts on the object at 2 s
(A) 105 N (B) 75 N (C) 55 N (D) 45 N (E) 35 N
44 A net force F = 10 + 6t2 is applied to a 30 kg cart that can move on a flat horizontal surface If the cart starts from rest what is its speed at 5 s
(A) 10 ms (B) 8 ms (C) 5 ms (D) 3 ms (E) 1 ms
45 Block of mass m moves to the right at a constant velocity v and collides elastically with another block of mass 3m Which of the following is the velocity of each block after the collision
Block m Block 3m
(A) Zero v
(B) v2 v2
(C) ndashv2 v2
(D) 3v2 v2
(E) ndashv2 3v2
46 A 40 kg skateboarder runs at a constant velocity of 12 ms and jumps of a
stationary skateboard with a mass of 8 kg What is the velocity of the
skateboard after the jump
(A) 12 ms (B) 90 ms (C) 60 ms (D) 20 ms (E) 10 ms
47 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves
at a constant velocity of 2 ms What is the velocity of the boat after the jump if the
diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the
boat
(A) 2 ms (B) 3 ms (C) 4 ms (D) 5 ms (E) 6 ms
48 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back
with a momentum of 6 kgms after the collision with the racket What is the change
in momentum of the tennis ball
(A) 1 kgms (B) 5 kgms (C) 6 kgms (D) 11 kgms 0 kgms
49 A light beach ball moving with a velocity 2 ms to the right collides elastically with a
stationary bowling ball After the collision the bowling ball remains stationary What is
the velocity of the beach ball after the collision
(A) 0 ms (B) 2 ms to the left (C) 4 ms to the left
(D) 3 ms to the left (E) 1 ms to the left
50 A of mass m moving at a constant speed v to the right collides elastically with
another ball of mass 3m moving to the left at a constant speed v What is the velocity
of ball m after the collision
(A) v (B) minus3
2v (C) minus
1
3v (D) 2v (E) -2v
Answer Key
1A 6B 11D 16A 21B 26D 31C 36A 41C 46E
2A 7A 12D 17E 22D 27A 32E 37C 42E 47B
3B 8D 13C 18E 23E 28E 33A 38D 43C 48D
4A 9C 14C 19C 24A 29B 34C 39B 44A 49B
5C 10A 15B 20B 25D 30B 35C 40D 45C 50E
31 Consider these two cases First a car moving at 40 mph hits another car of equal mass moving at 40 mph in the opposite direction
Second a car moving at 40 mph hits a stationary steel wall
The collision time is the same for the two cases and the collisions are both inelastic In which of these cases would result in the greatest impact force
(A) Hitting the wall (B) Hitting the other car (C) The force would be the same in both cases (D) More information is needed (E)None of the above are true
Questions 32-33
A mass M moving with speed v collides with an uncompressed stationary spring of mass M with a spring constant K The surface is frictionless
32 What will be the maximum compression of the spring
(A) vradic119872119870 (B) vradic1198724119870 (C) 119907
2 radic3119872119870 (D) vradic2119872119870 (E) vradic1198722119870
33 What is the speed of the spring after the collision
(A) v (B) 119907 2frasl (C) 119907 4frasl (D) 2v (E) 119907 3frasl
Questions 34-35
A 6 kg mass is moving at 12 ms in the +x direction is acted upon by a force with magnitude given as a function of time by the graph
34 Find the magnitude of the change in momentum from time t = 0 to time t = 8 s
(A) 12 kg ms (B) 24 kg ms (C) 36 kg ms (D) 40 kg ms (E) 52 kg ms
35 What is the velocity of the mass after the force has stopped acting
(A) 6 ms (B) 10 ms (C) 18 ms (D) 24 ms (E) 40 ms
36 A wire is bent into the shape as shown above Which of the following best represents the coordinates of the center of mass
(A) (1314 67) (B) (87 67) (C) (1314 87) (D) (11) (E) (167)
37 A block of mass m is moving with speed vo to the right on a frictionless surface when it explodes into two pieces of unequal mass One piece of the mass 3m4 moves with a speed vo2 to the left while the other piece of the object moves with velocity
(A) vo2 (B) 2vo3 (C) 11vo2 (D) 7vo5 (E) 2vo
38 Two blocks with masses m and 2m are placed on a horizontal frictionless surface There is a compressed spring between the block and after the spring is released 2m block moves to the right with a speed of v What is the total work done by the spring on the system of two blocks
(A) Zero (B) mv2 (C) 2mv2 (D) 3mv2 (E) mv
39 A railway artillery gun of mass 1400 tonnes is initially at rest on a horizontal surface when fires a 7 tonnes shell with a velocity of 800 ms at an angle of 60deg What is the speed of the gun immediately after the shell is fired
(A) Zero (B) 2 ms (C) 4 ms (D) 5 ms (E) 7 ms
40 Two equal forces are exerted for the same length of time on two blocks with different masses m1 and m2 (m2 gtm1) Which of the following will describe the change is kinetic energy of the blocks
(A) Blocks have the same change in kinetic energy
(B) The change in kinetic energy of each block is zero
(C) Block m2 has greater change in kinetic energy
(D) Block m1 has greater change in kinetic energy
(E) Non from the above is correct
41 A boy launches a 20 g dart in horizontal by a spring gun from a balcony 45 m above the ground The dart lands 15 m away from the balcony If the length of the gunrsquos barrel is 10 cm what is the average horizontal force applied by the spring
(A) 10 N (B) 20 N (C) 25 N (D) 50 N (E) 75 N
42 A mall of mass m is dropped from a height of ho The ball hits the floor and bounces to a height of h What is the magnitude of impulse exerted on the ball by the floor
(A) mgh (B) 2mgh (C) radic2119898119892ℎ (D) 119898radic2119892(ℎ minus ℎ119900) (E) 119898radic2119892(ℎ + ℎ119900)
43 A 5 kg object starts from rest on a flat horizontal surface and moves in a straight line The velocity as a function of time is given by v = 3t + 2t2 What is the magnitude of instantaneous force that acts on the object at 2 s
(A) 105 N (B) 75 N (C) 55 N (D) 45 N (E) 35 N
44 A net force F = 10 + 6t2 is applied to a 30 kg cart that can move on a flat horizontal surface If the cart starts from rest what is its speed at 5 s
(A) 10 ms (B) 8 ms (C) 5 ms (D) 3 ms (E) 1 ms
45 Block of mass m moves to the right at a constant velocity v and collides elastically with another block of mass 3m Which of the following is the velocity of each block after the collision
Block m Block 3m
(A) Zero v
(B) v2 v2
(C) ndashv2 v2
(D) 3v2 v2
(E) ndashv2 3v2
46 A 40 kg skateboarder runs at a constant velocity of 12 ms and jumps of a
stationary skateboard with a mass of 8 kg What is the velocity of the
skateboard after the jump
(A) 12 ms (B) 90 ms (C) 60 ms (D) 20 ms (E) 10 ms
47 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves
at a constant velocity of 2 ms What is the velocity of the boat after the jump if the
diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the
boat
(A) 2 ms (B) 3 ms (C) 4 ms (D) 5 ms (E) 6 ms
48 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back
with a momentum of 6 kgms after the collision with the racket What is the change
in momentum of the tennis ball
(A) 1 kgms (B) 5 kgms (C) 6 kgms (D) 11 kgms 0 kgms
49 A light beach ball moving with a velocity 2 ms to the right collides elastically with a
stationary bowling ball After the collision the bowling ball remains stationary What is
the velocity of the beach ball after the collision
(A) 0 ms (B) 2 ms to the left (C) 4 ms to the left
(D) 3 ms to the left (E) 1 ms to the left
50 A of mass m moving at a constant speed v to the right collides elastically with
another ball of mass 3m moving to the left at a constant speed v What is the velocity
of ball m after the collision
(A) v (B) minus3
2v (C) minus
1
3v (D) 2v (E) -2v
Answer Key
1A 6B 11D 16A 21B 26D 31C 36A 41C 46E
2A 7A 12D 17E 22D 27A 32E 37C 42E 47B
3B 8D 13C 18E 23E 28E 33A 38D 43C 48D
4A 9C 14C 19C 24A 29B 34C 39B 44A 49B
5C 10A 15B 20B 25D 30B 35C 40D 45C 50E
36 A wire is bent into the shape as shown above Which of the following best represents the coordinates of the center of mass
(A) (1314 67) (B) (87 67) (C) (1314 87) (D) (11) (E) (167)
37 A block of mass m is moving with speed vo to the right on a frictionless surface when it explodes into two pieces of unequal mass One piece of the mass 3m4 moves with a speed vo2 to the left while the other piece of the object moves with velocity
(A) vo2 (B) 2vo3 (C) 11vo2 (D) 7vo5 (E) 2vo
38 Two blocks with masses m and 2m are placed on a horizontal frictionless surface There is a compressed spring between the block and after the spring is released 2m block moves to the right with a speed of v What is the total work done by the spring on the system of two blocks
(A) Zero (B) mv2 (C) 2mv2 (D) 3mv2 (E) mv
39 A railway artillery gun of mass 1400 tonnes is initially at rest on a horizontal surface when fires a 7 tonnes shell with a velocity of 800 ms at an angle of 60deg What is the speed of the gun immediately after the shell is fired
(A) Zero (B) 2 ms (C) 4 ms (D) 5 ms (E) 7 ms
40 Two equal forces are exerted for the same length of time on two blocks with different masses m1 and m2 (m2 gtm1) Which of the following will describe the change is kinetic energy of the blocks
(A) Blocks have the same change in kinetic energy
(B) The change in kinetic energy of each block is zero
(C) Block m2 has greater change in kinetic energy
(D) Block m1 has greater change in kinetic energy
(E) Non from the above is correct
41 A boy launches a 20 g dart in horizontal by a spring gun from a balcony 45 m above the ground The dart lands 15 m away from the balcony If the length of the gunrsquos barrel is 10 cm what is the average horizontal force applied by the spring
(A) 10 N (B) 20 N (C) 25 N (D) 50 N (E) 75 N
42 A mall of mass m is dropped from a height of ho The ball hits the floor and bounces to a height of h What is the magnitude of impulse exerted on the ball by the floor
(A) mgh (B) 2mgh (C) radic2119898119892ℎ (D) 119898radic2119892(ℎ minus ℎ119900) (E) 119898radic2119892(ℎ + ℎ119900)
43 A 5 kg object starts from rest on a flat horizontal surface and moves in a straight line The velocity as a function of time is given by v = 3t + 2t2 What is the magnitude of instantaneous force that acts on the object at 2 s
(A) 105 N (B) 75 N (C) 55 N (D) 45 N (E) 35 N
44 A net force F = 10 + 6t2 is applied to a 30 kg cart that can move on a flat horizontal surface If the cart starts from rest what is its speed at 5 s
(A) 10 ms (B) 8 ms (C) 5 ms (D) 3 ms (E) 1 ms
45 Block of mass m moves to the right at a constant velocity v and collides elastically with another block of mass 3m Which of the following is the velocity of each block after the collision
Block m Block 3m
(A) Zero v
(B) v2 v2
(C) ndashv2 v2
(D) 3v2 v2
(E) ndashv2 3v2
46 A 40 kg skateboarder runs at a constant velocity of 12 ms and jumps of a
stationary skateboard with a mass of 8 kg What is the velocity of the
skateboard after the jump
(A) 12 ms (B) 90 ms (C) 60 ms (D) 20 ms (E) 10 ms
47 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves
at a constant velocity of 2 ms What is the velocity of the boat after the jump if the
diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the
boat
(A) 2 ms (B) 3 ms (C) 4 ms (D) 5 ms (E) 6 ms
48 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back
with a momentum of 6 kgms after the collision with the racket What is the change
in momentum of the tennis ball
(A) 1 kgms (B) 5 kgms (C) 6 kgms (D) 11 kgms 0 kgms
49 A light beach ball moving with a velocity 2 ms to the right collides elastically with a
stationary bowling ball After the collision the bowling ball remains stationary What is
the velocity of the beach ball after the collision
(A) 0 ms (B) 2 ms to the left (C) 4 ms to the left
(D) 3 ms to the left (E) 1 ms to the left
50 A of mass m moving at a constant speed v to the right collides elastically with
another ball of mass 3m moving to the left at a constant speed v What is the velocity
of ball m after the collision
(A) v (B) minus3
2v (C) minus
1
3v (D) 2v (E) -2v
Answer Key
1A 6B 11D 16A 21B 26D 31C 36A 41C 46E
2A 7A 12D 17E 22D 27A 32E 37C 42E 47B
3B 8D 13C 18E 23E 28E 33A 38D 43C 48D
4A 9C 14C 19C 24A 29B 34C 39B 44A 49B
5C 10A 15B 20B 25D 30B 35C 40D 45C 50E
40 Two equal forces are exerted for the same length of time on two blocks with different masses m1 and m2 (m2 gtm1) Which of the following will describe the change is kinetic energy of the blocks
(A) Blocks have the same change in kinetic energy
(B) The change in kinetic energy of each block is zero
(C) Block m2 has greater change in kinetic energy
(D) Block m1 has greater change in kinetic energy
(E) Non from the above is correct
41 A boy launches a 20 g dart in horizontal by a spring gun from a balcony 45 m above the ground The dart lands 15 m away from the balcony If the length of the gunrsquos barrel is 10 cm what is the average horizontal force applied by the spring
(A) 10 N (B) 20 N (C) 25 N (D) 50 N (E) 75 N
42 A mall of mass m is dropped from a height of ho The ball hits the floor and bounces to a height of h What is the magnitude of impulse exerted on the ball by the floor
(A) mgh (B) 2mgh (C) radic2119898119892ℎ (D) 119898radic2119892(ℎ minus ℎ119900) (E) 119898radic2119892(ℎ + ℎ119900)
43 A 5 kg object starts from rest on a flat horizontal surface and moves in a straight line The velocity as a function of time is given by v = 3t + 2t2 What is the magnitude of instantaneous force that acts on the object at 2 s
(A) 105 N (B) 75 N (C) 55 N (D) 45 N (E) 35 N
44 A net force F = 10 + 6t2 is applied to a 30 kg cart that can move on a flat horizontal surface If the cart starts from rest what is its speed at 5 s
(A) 10 ms (B) 8 ms (C) 5 ms (D) 3 ms (E) 1 ms
45 Block of mass m moves to the right at a constant velocity v and collides elastically with another block of mass 3m Which of the following is the velocity of each block after the collision
Block m Block 3m
(A) Zero v
(B) v2 v2
(C) ndashv2 v2
(D) 3v2 v2
(E) ndashv2 3v2
46 A 40 kg skateboarder runs at a constant velocity of 12 ms and jumps of a
stationary skateboard with a mass of 8 kg What is the velocity of the
skateboard after the jump
(A) 12 ms (B) 90 ms (C) 60 ms (D) 20 ms (E) 10 ms
47 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves
at a constant velocity of 2 ms What is the velocity of the boat after the jump if the
diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the
boat
(A) 2 ms (B) 3 ms (C) 4 ms (D) 5 ms (E) 6 ms
48 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back
with a momentum of 6 kgms after the collision with the racket What is the change
in momentum of the tennis ball
(A) 1 kgms (B) 5 kgms (C) 6 kgms (D) 11 kgms 0 kgms
49 A light beach ball moving with a velocity 2 ms to the right collides elastically with a
stationary bowling ball After the collision the bowling ball remains stationary What is
the velocity of the beach ball after the collision
(A) 0 ms (B) 2 ms to the left (C) 4 ms to the left
(D) 3 ms to the left (E) 1 ms to the left
50 A of mass m moving at a constant speed v to the right collides elastically with
another ball of mass 3m moving to the left at a constant speed v What is the velocity
of ball m after the collision
(A) v (B) minus3
2v (C) minus
1
3v (D) 2v (E) -2v
Answer Key
1A 6B 11D 16A 21B 26D 31C 36A 41C 46E
2A 7A 12D 17E 22D 27A 32E 37C 42E 47B
3B 8D 13C 18E 23E 28E 33A 38D 43C 48D
4A 9C 14C 19C 24A 29B 34C 39B 44A 49B
5C 10A 15B 20B 25D 30B 35C 40D 45C 50E
45 Block of mass m moves to the right at a constant velocity v and collides elastically with another block of mass 3m Which of the following is the velocity of each block after the collision
Block m Block 3m
(A) Zero v
(B) v2 v2
(C) ndashv2 v2
(D) 3v2 v2
(E) ndashv2 3v2
46 A 40 kg skateboarder runs at a constant velocity of 12 ms and jumps of a
stationary skateboard with a mass of 8 kg What is the velocity of the
skateboard after the jump
(A) 12 ms (B) 90 ms (C) 60 ms (D) 20 ms (E) 10 ms
47 An 80 kg diver jumps off a moving boat The boat has a mass of 400 kg and moves
at a constant velocity of 2 ms What is the velocity of the boat after the jump if the
diver jumps with a velocity of 3 ms in opposite direction to the initial velocity of the
boat
(A) 2 ms (B) 3 ms (C) 4 ms (D) 5 ms (E) 6 ms
48 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back
with a momentum of 6 kgms after the collision with the racket What is the change
in momentum of the tennis ball
(A) 1 kgms (B) 5 kgms (C) 6 kgms (D) 11 kgms 0 kgms
49 A light beach ball moving with a velocity 2 ms to the right collides elastically with a
stationary bowling ball After the collision the bowling ball remains stationary What is
the velocity of the beach ball after the collision
(A) 0 ms (B) 2 ms to the left (C) 4 ms to the left
(D) 3 ms to the left (E) 1 ms to the left
50 A of mass m moving at a constant speed v to the right collides elastically with
another ball of mass 3m moving to the left at a constant speed v What is the velocity
of ball m after the collision
(A) v (B) minus3
2v (C) minus
1
3v (D) 2v (E) -2v
Answer Key
1A 6B 11D 16A 21B 26D 31C 36A 41C 46E
2A 7A 12D 17E 22D 27A 32E 37C 42E 47B
3B 8D 13C 18E 23E 28E 33A 38D 43C 48D
4A 9C 14C 19C 24A 29B 34C 39B 44A 49B
5C 10A 15B 20B 25D 30B 35C 40D 45C 50E
48 A tennis ball approaches a racket with a momentum of 5 kgms and bounces back
with a momentum of 6 kgms after the collision with the racket What is the change
in momentum of the tennis ball
(A) 1 kgms (B) 5 kgms (C) 6 kgms (D) 11 kgms 0 kgms
49 A light beach ball moving with a velocity 2 ms to the right collides elastically with a
stationary bowling ball After the collision the bowling ball remains stationary What is
the velocity of the beach ball after the collision
(A) 0 ms (B) 2 ms to the left (C) 4 ms to the left
(D) 3 ms to the left (E) 1 ms to the left
50 A of mass m moving at a constant speed v to the right collides elastically with
another ball of mass 3m moving to the left at a constant speed v What is the velocity
of ball m after the collision
(A) v (B) minus3
2v (C) minus
1
3v (D) 2v (E) -2v
Answer Key
1A 6B 11D 16A 21B 26D 31C 36A 41C 46E
2A 7A 12D 17E 22D 27A 32E 37C 42E 47B
3B 8D 13C 18E 23E 28E 33A 38D 43C 48D
4A 9C 14C 19C 24A 29B 34C 39B 44A 49B
5C 10A 15B 20B 25D 30B 35C 40D 45C 50E