Unit 1Unit 1MotionMotion

ProjectileProjectile

MotionMotion

Motion to DateMotion to Date

Uniform MotionUniform Motion Accelerated MotionAccelerated Motion Relative MotionRelative Motion

Uniform MotionUniform Motion

Motion with a constant velocityMotion with a constant velocity

Equation: Equation: d

vt

- Constant speed- Same direction

ProblemsProblems

1. An airplane travels 300 km in 1.25 1. An airplane travels 300 km in 1.25 hours. Find its speed.hours. Find its speed.

2. A hunter travels 3 km [N] in 0.75 h 2. A hunter travels 3 km [N] in 0.75 h and 2 km [E] in 30 minutes. Find and 2 km [E] in 30 minutes. Find her average:her average:

A) speedA) speed

B) velocityB) velocity

3.3. A kayaker can travel at 4 m/s relative to A kayaker can travel at 4 m/s relative to the water.the water.

If she is in a river that has a current of 2 If she is in a river that has a current of 2 m/s [S] find her velocity with respect to m/s [S] find her velocity with respect to (wrt) the (i) shore and (ii) water (wrt) the (i) shore and (ii) water

if she headsif she heads

A) UpstreamA) Upstream

B) DownstreamB) Downstream

C) Directly across the streamC) Directly across the stream

AppletApplet VECTOR REVIEW??VECTOR REVIEW?? Vector AdditionVector Addition

– http://hyperphysics.phy-astr.gsu.edu/hbase/vect.htmlhttp://hyperphysics.phy-astr.gsu.edu/hbase/vect.html

Suppose the river is 50 m wide. How Suppose the river is 50 m wide. How far will the kayak land downstream far will the kayak land downstream on the other side?on the other side?

4.4.Suppose the kayaker want to land directly Suppose the kayaker want to land directly across the stream. across the stream.

A) Find the angle she would have to point to A) Find the angle she would have to point to do so.do so.

B) Find the time it would take for her to get B) Find the time it would take for her to get to the other side.to the other side.

Accelerated motionAccelerated motion

Motion with changing velocityMotion with changing velocity Examples?Examples?

Accelerated motion occurs when Accelerated motion occurs when either either – the speed is changing the speed is changing

speeding up or slowing downspeeding up or slowing down

– Direction is changingDirection is changingCurved motionCurved motion

Equations for accelerated motionEquations for accelerated motion

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Formula SheetFormula Sheet

ExamplesExamples

1.1. A cyclist can accelerate from 10. A cyclist can accelerate from 10. km/h to 30. km/h in 3.5s. Find his km/h to 30. km/h in 3.5s. Find his acceleration.acceleration.

2.2. A glove is dropped from a chairlift A glove is dropped from a chairlift and hits the ground 2 seconds later.and hits the ground 2 seconds later.

A)A) How high is the chairlift?How high is the chairlift?

B)B) How fast was the glove travelling How fast was the glove travelling when it hit the ground?when it hit the ground?

3.3. Police measure skid marks to Police measure skid marks to determine the speed of a car just determine the speed of a car just before skidding started. If the before skidding started. If the acceleration of car is 7.5 m/sacceleration of car is 7.5 m/s22 (based (based on the surface condition of the road) on the surface condition of the road) and the length of the skid is 45 m, and the length of the skid is 45 m, determine the speed the car was determine the speed the car was traveling before locking the tires. traveling before locking the tires. (Assuming the car was stopped at (Assuming the car was stopped at the end of the skid.)the end of the skid.)

4.4. Determine the speed the object Determine the speed the object hits the ground.hits the ground.

100

m

The object has an initial upwards velocity of 25 m/s.

5.5. Determine the time it would take Determine the time it would take a rock to hit the ground if:a rock to hit the ground if:

A) it was dropped from a height of 2 m.A) it was dropped from a height of 2 m.

B) thrown upwards at 20 m/s from the 2 B) thrown upwards at 20 m/s from the 2 m height. m height.

C) thrown downwards at 20 m/s from C) thrown downwards at 20 m/s from the 2 m height. the 2 m height.

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What is projectile motion?What is projectile motion?

Anything that is thrown that has Anything that is thrown that has some some _____________ _____________ motion.motion.– Jumping on a Jumping on a _____, ___, __________, _____, ___, __________,

__________________, skakeboards, __________, , skakeboards, __________, horses, ______.horses, ______.

– Running off a Running off a ________________________________..– __________________________________________ that are shot. that are shot.– Throwing Throwing ____________________ or or ______________________, or , or

kicking a kicking a ____________________________..

A projectile is any object which, once A projectile is any object which, once projected, continues its motion by its projected, continues its motion by its own own ________________ and is influenced only and is influenced only by the downward force of by the downward force of ________________..

It is important to study this if you It is important to study this if you want objects to land in certain spotswant objects to land in certain spots

Movie 1Movie 1

Movie 2Movie 2

What describes the path of a What describes the path of a projectile?projectile?– ____________________________________

In 3204 projectile motion is limited to In 3204 projectile motion is limited to negligible negligible __________________________– http://physics.usask.ca/~pywell/p121/http://physics.usask.ca/~pywell/p121/

Notes/projectile/projectile.htmlNotes/projectile/projectile.html– MythbustersMythbusters

Horizontal motion (Horizontal motion (____-direction) is -direction) is ________________________ (no (no __________________________))

Vertical motion (Vertical motion (____-direction) is -direction) is ______________________________ ( (________________________))

Distance travelled in the x-direction Distance travelled in the x-direction is defined as is defined as ________.________.

Time is the Time is the ____________ in both the x and y in both the x and y direction.direction.

Equations for Projectile MotionEquations for Projectile Motion

Horizontal MotionHorizontal Motion

(x-direction)(x-direction)

Uniform MotionUniform Motion

Vertical MotionVertical Motion

(y-direction)(y-direction)

Accelerated MotionAccelerated Motion

Components of VelocityComponents of Velocity

Mathematically determine the Mathematically determine the components of velocity at certain components of velocity at certain points along a projectile’s motion.points along a projectile’s motion.– AppletApplet

Types of Projectile MotionTypes of Projectile Motion

______________________________ moving off a cliff moving off a cliff– ((__________________________________________))

Projected motion at Projected motion at ________________________, and , and lands at a pointlands at a point

Projected motion at an angle Projected motion at an angle , and , and lands at a point:lands at a point:

A) level with launchA) level with launch B) Above B) Above launchlaunch

C) below launchC) below launch

Projectiles with zero vertical Projectiles with zero vertical velocityvelocity

Worksheet 1Worksheet 1

Projectiles with NON zero vertical Projectiles with NON zero vertical velocityvelocity

Worksheet 2Worksheet 2

Worksheet 3Worksheet 3

AssignmentAssignment

The Physics of JugglingThe Physics of Juggling

AppletApplet Air resistanceAir resistance

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