slides off. a) What is the radial acceleration of the coin at 40 rpm? b) What is the coefficient of...

(HS Engineers( للعديد من المواد على قناتكم )مجاناشرح فيديو )

net.hs-eng ,com.hs-eng بالموقعين مجانا النوتات متوفرة @hs.com-enginfo 26044449 م. حمادة شعبان

Mid I, June 2014

A 4-N net force acts on a ball (𝑚 = 0.2 𝑘𝑔)

and keeps it in a uniform circular motion of

radius 15 cm.

a) What is the magnitude of the linear

velocity of the ball?

b) What is the period of this circular motion.



Mid I, March 2014

A ball of mass 𝑚 = 0.2 𝑘𝑔is connected to

a string of length 1.6 m. The ball is rotated

in a horizontal circular path with the

constant speed of 2.0 m/s.

a) Determine the tension in the string.

b) What is the maximum frequency that

ball can have if the string can withstand

a maximum tension of 5.0 N?



Mid I, October 2013

An ultracentrifuge rotates at 60,000rpm.

a) Find the speed (in m/s) of a particle at

8cm from the axis of rotation.

b) What is the acceleration of this particle

in terms of (g = 9.8 m/s2)?

(HS Engineersللعديد من المواد على قناتكم )( مجاناشرح فيديو )


Mid I, June 2013

The Earth rotates around its axis once in

every 24 hours. What is the angular speed

and the centripetal acceleration of a person

at the equator? (The radius of the Earth at

the equation is 𝑅 = 6400 𝑘𝑚).

(HS Engineersالمواد على قناتكم )( للعديد من مجاناشرح فيديو )


Phy121-Mid2-April2013

The Ferris wheel, shown in the figure, has a

radius of 7.5 m and is rotating at a constant

linear speed, 𝑣. If the apparent weight of a

passenger at the top position is half his apparent

weight at the bottom position, calculate:

a) the magnitude of the linear speed, 𝑣(in m/s),

and

b) the number of revolutions that the Ferris

wheel makes in one minute.



Mid I, June 2012

A space station of diameter 80 m is turning about

its axis at a constant rate. If the acceleration of

the outer rim of the station is 2.5 m/s2?

a) Find the speed of the station.

b) What is the period of revolution of the

space station?

c) How many revolutions per minute does the

station make?



Mid I, March 2012

Ali and Bader sit on a horizontal bar of length 2m, which

is connected to a vertical post as shown in the figure. The

post rotates at 10 rpm (revolution per minute).

a) Circle the correct answers:

If the linear speeds of Ali and Bader are 𝑣𝐴 , 𝑣𝐵

respectively, then

(i)𝑣𝐴 = 𝑣𝐵(ii)𝑣𝐴 < 𝑣𝐵(iii)𝑣𝐴 > 𝑣𝐵

If the periods of the circular motions of Ali and

Bader are 𝑇𝐴, and 𝑇𝑦 respectively, then

(i)𝑇𝐴 = 𝑇𝐵(ii)𝑇𝐴 < 𝑇𝐵(iii)𝑇𝐴 > 𝑇𝐵

b) Calculate the linear speed of Ali (in m/s).

c) Calculate the centripetal (or radial) force on Ali if

his mass is 40 kg.



Mid I, Oct 2011

Passengers feel weightless at the top of the

rotating Ferris wheel shown below. What is

the minimum constant rpm (revolutions per

minute) of the Ferris wheel?



Mid I, July 2011

A flat block of mass, 𝑚 = 5 𝑘𝑔, is being

rotated in a circle on a frictionless table.

The radius of rotation, 𝑟 = 32 𝑐𝑚, is held

constant by attaching a light cord between

𝑚 and another mass, 𝑀 = 1 𝑘𝑔, as shown

in figure. Find the speed of rotation.



Mid I, March 2011

A ball connected to a 0.5 m long string is

rotating in a circular motion. If the frequency

of the motion is 500 rpm, calculate the

centripetal acceleration (in m/s2).

أفضل صداقة يمكنها االستمرار هي

.التي يستفيد منها كافة األصدقاء



Mid I, March 2011

A 30 kg child is riding a roller coaster that

has a radius of 5 m. If the normal force on

the child the bottom of her circular motion

is 600 N, what is her speed (in m/s)?

ستأتي الفرص حتما، المهم

.أن نكون جاهزين

First, Fall 2011

A particle is at a distance of 15 cm from the axis of rotation of a centrifuge. Its centripetal acceleration is 1.4 x 104 m/s2.

Calculate the frequency of rotation of the centrifuge. Express the result in unit of revolutions per minute.

Ci(, -· r

I u I '1 - ~ 1r ( -·· I~) '71 0 - V

I

-®, eng-hs.net ~ HS Engineers £J ~ hs _ enginee1'S M [email protected] 00965-94444260 6~ oJI.A:I,,. ·f'


net.hs-eng,com.hs-engبالموقعين مجانا النوتات متوفرة hs.com-enginfo@26044449م. حمادة شعبان

Mid I, Fall 2011

A ball on the end of a string is revolved at

a uniform rate in a vertical circle of

radius , as shown in the figure.

If its speed is 5 m/s and its mass is , calculate the tension in the string when the

ball is (a) at the top of its path, and (b) at

the bottom of its path.

eng-hs.net HS Engineers hs_engineers [email protected] 00965-94444260 م. حمادة شعبان

شروح الفيديو تتوفر على قناتكم

HS Engineers

Mastering Problems

Physics 121

http://instagram.com/hs_engineers

https://www.youtube.com/channel/UC5D-K3_8dCEpSRlXum1kxwA

http://www.eng-hs.net

http://twitter.com/hs_engineers

5-2-Chapter s

\\'lliich of the follo,\iin~ point to\\-"ards the. center of the. circl.e - 4

in unifor111 circular motion? (a-} Acce·leration .. ~ ( b . .} \lel.ocitJ{'acceleration .. net force. " ( c) \lel.oci ~ ~ ccelera1 ti.on .. (ti) \fel.ocitifne.t force .. (e) ,l" _cceleration, net force:._ ~

- - - ~--~~ - ---~-----·-, . Chapter 5 i ~,...~~:>-"'-~~J

i\ Ping-Pong ball is shot into a circular tube that is Iving ..._.,. iii,,...... •' .,.___

flat (horizontal) on a tabletop. When the Ping-Pong ball exits the tube .. ,.vhich path \viii it folio,~ in Fig. 5-35? ,.__,

FIGURE5-35 ~ifisConceptual Question 3.

(a)

MIE--· .... (tJ4 (d)

(e) ball!euters

Chapters

5-J-\ l\. car drives at steady speed aeound a perfectly circular tTack. (a) The cal"~s acceleration is zero. ~ CX.y ~ ~ (b) TI1e ne.t force on the car is zero. ,< f ::. ~ Ay

(c) Both the acoe:leration and nel force on the car poh1J Ollt\\rard~ )( ~

(d ) Both the acceleration and net force on the cat" point in\vard. V

({! ) If there is no friction~ the acceleratioUJ is oul,\•·a.rd.. X

5-S .. A child ,vbirls a ball in a vertical circle .. A.ss1.1n1ing the speed of the ball is co11stant ( an approximation)., when would the tension in the cord connected to the ball be greatest? (a ) .. ~t the top of the circle.. ~.:,,, l ( b) At the botto111 of the circle'" ~ ,( c) A little after the botton1 of the circle ,,rhen the ball is

clin1bing. (d) A little before the botton1 of the circle ,vhen tile baU is

descending quickly_ ( e) Novi here; the cord is stretched the sa.n1e amount at all

points~

V. '-'-

J, ~ 2

L. F - W\ V,

- .,.. ho~ T-~_, - ~ "~ 41 - ,-

' : •p T-1-~_, - W\ ",1.. _HjJ\ - -r Y\~lJ-, tefl T-= ~ "·t. -~~~ -r

( -Chapter 5 ..

6. In a rotating vertical cylinder (Rotor-ride) a rider finds herself pressed \Vith her back to the rotating vvall. \Vl1ich is the correct free-body diagra1n for her (Fig. 5-36)?

(:?

,y.~ ~ ,/:..;, ,, ··•

"<'L) .·.

~ (d)

AGURE 5-36 MisConceptual Question 6.

... , (e)

~ eng-hs.net ~ HS Engineers Cl~ hs_engineet'S M [email protected] ~ 00965-94444260 ~ 0~-i"

C~s 6. In a rotating vertical cylinder (Rotor-ride) a rider finds

herself pressed ,vith her back to the rotating wall. Which is the correct free-body diagram for her (Fig. 5-36)?

V IGURE 5-36 MisConceptual Question 6-,,,,,

f\ ~ >..,- ~,_.> ~-e ~_)) •

W eng-hs.net ~ HS Engineers CJ(® hs_engineers M [email protected] 00965-94444260 w~ o.1i- .e,

•

Chapter 5 i

TI1e :rvtoon does not crash into the Eartl1 because: (a) the net force on it is zero'° x (b) it is beyond the n1ain pull of the Earth's gravity~ X ( c) it is being pulled by the Sun as \Veil as by the Earth. >( ( d) it is freely faUii1g but it has a higl1 tangential velocity.

F =

( Chapt~r 5 J

4. (II) What is the magnitude of the acceleration of a speck of clay on the edge of a potter's wheel turning at 45 rpm. ( revolutions per minute) if the wheel's diameter is 35 cm?

S-=

--

@- eng-hs.net [;l HS Engineers Cl(® hs_engineers t--(1 [email protected] 00965-94444260 w~ ~~i.- ·<'

Chapter 5

18. (II) Tarzan plans to cross a gorge by swinging in an arc from a hanging vine (Fig. 5- 42). If his arms are capable of exerting a force of 1150 N on the vine, what is the maximum speed he can tolerate at the lowest point of his swing? His mass is 78 kg and the vine is 4.7 m long.

FIGURE 5-42 Problem 18.

,@ eng-hs.net C HS Engineers CJ(® hs_engineers

0.< F

[email protected] 00965-94444260 CJ~ oJt- ·i'

slides off. a) What is the radial acceleration of the coin at 40 rpm? b) What is the coefficient of...

Documents

Transcript of slides off. a) What is the radial acceleration of the coin at 40 rpm? b) What is the coefficient of...