1

Motion

Chapter 9 pages 281-306

We are learning to: explain motion

We are looking for: an act, process, or instance of changing position through time.

3

Describing and Measuring Motion

An object is in motion if the distance from another object is changing.

Reference point is a place or object used for comparison to determine if something is in motion.

4

Motion

An object is in motion if it changes position relative to a reference point.

The standard measurement for distance is a meter.

The rate of change in motion is called speed.

Which of the following describes motion?

0% 0%0%0%

A. A change in mass over time

B. A change in position over mass

C. A change in distance over time

D. A change in mass over distance

How do you know that the car is in motion?

0% 0%0%

A. The distance between the building and car changes.

B. The time it takes the car to move is constant.

C. The distance between the building and the car stays constant.

What is the SI or metric unit for distance?

Mile

s

Gram

s

Meter

Feet

0% 0%0%0%

a) Miles

b) Grams

c) Meter

d) Feet

What is used for comparison to tell if an object is in motion?

directi

on

refe

rence point

Speed

velocit

y

0% 0%0%0%

a) direction

b) reference point

c) Speed

d) velocity

Do this: From what you know about motion- write a paragraph explaining this video clip

We are learning to: explain the difference between speed and

velocity 

We are looking for: Speed = change in distance/ change in

time. Velocity = speed + direction of an object. Velocity has a

direction, while speed does not.

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Speed

The speed of an object is the distance the object travels in one unit of time.

Speed is calculated by dividing the distance by the time:

Speed=distance/time

v=d/t

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Types of Speed

Constant speed is the speed of an object that does not change.

Average speed is an average of all the speeds that an object travels during long period of time.

13

Speed vs. Velocity

Velocity is speed with a direction.

An object that is traveling at a constant speed can change in velocity if the direction is changing.

What is the formula needed to calculate speed of an object?

distance

x tim...

distance

/ tim...

time / dist

anc...

accelera

tion x...

I need help!

0% 0% 0%0%0%

A. distance x time

B. distance / time

C. time / distance

D. acceleration x time

E. I need help!

Joe Shmoe walks 30 meters in 10 seconds. What was his speed?

0% 0%0%0%

A. 5 meters/second

B. 3 seconds/meter

C. 3 meters/second

D. I need help!

What is the only difference between speed and velocity?

0% 0% 0%0%0%

A. Speed is more complex while velocity is less complex.

B. Velocity is time divided by distance and speed is distance divided by time.

C. Velocity requires a direction while speed does not.

D. Speed and velocity are calculated differently.

E. I need help!

Which of the following is an acceptable unit for velocity?

0% 0% 0%0%0%

A. Meters per second

B. Feet per hour

C. Miles per hour South

D. Miles per hour

E. I need help!

Please copy circle and do this.

Speed

Fill in three words that closely relate to the one word given.

Write a paragraph explaining the significance of each word and how they fit together to form a concept?

We are learning to: explain the difference between speed and velocity

and interpret graphs. 

We are looking for: Speed = change in distance/ change in time. Velocity =

speed + direction of an object. Velocity has a direction, while speed

does not.

20

Graphing Motion

Time is on the x-axis of the graph.

Distance is on the y-axis of the graph.

The steepness of a line on a graph is called the slope. The faster the motion, the

steeper the slope. A horizontal line

represents an object that is not in motion.

You are asked to create a graph that shows the speed of an object. What should be plotted on the x and y axes?

Y axis

= speed; X

axis = time

Y axis

= time; X axis

= di...

Y axis

= distance

; X axis

...

Y axis

= time; X axis

= ac...

4% 0%

93%

4%

A. Y axis = speed; X axis = time

B. Y axis = time; X axis = distance

C. Y axis = distance; X axis = time

D. Y axis = time; X axis = acceleration

What is this graph showing?

14%

0%4%

82%A. A person walking at varying

speeds.

B. A person walking at a constant speed and then stopping to rest.

C. A person standing still.

D. A person walked three miles.

What does this graph show?

The object is

not moving.

The object is

moving a

t..

The object is

moving a

t..

The object is

moving a

t ...

0% 0%4%

96%

A. The object is not moving.

B. The object is moving at a constant speed.

C. The object is moving at a constant speed then stopped to rest.

D. The object is moving at varying speeds.

What does a steep slope of a line on a distance time graph indicate?

93%

0%0%7%

A. Speed is fast

B. Speed is slow

C. The object is not moving

D. Speed is changing

Graphing Activity

Construct a graph in your notes using the data to the right. Be sure to label the x and y axis with correct units.

DISTANCE (M) TIME (S)

0 0

1 1

3 2

5 3

5 4

5 5

6 6

7 7

8 8

26

Acceleration

Chapter 9, Section 3.

27

What is acceleration?

Acceleration is the rate at which velocity changes.

Acceleration refers to: Increasing speedDecreasing speedChanging direction

28

Calculating Acceleration

Acceleration=vf-vi/tvf is final velocity

vi is initial velocity

t is time

29

Graphing Acceleration

Time is on the x-axisSpeed is on the y-axisGraphed line rises the

same amount each second shows a linear relationship.

Graph of distance versus time is a curved line and shows a nonlinear relationship.

30

Which of the following is NOT an example of acceleration?

0% 0%0%0%

A. Walking in a straight line at a constant speed

B. Approaching a stop sign

C. A ball rolling down a hill

D. Turning around a corner at a constant speed

10

31

Slowing down is referred to as…

Posi

tive

Accel

erat

ion

Neg

ativ

e Acc

eler

atio

n

Dec

eler

atio

n

Both

B. a

nd C

.

0% 0%0%0%

A. Positive Acceleration

B. Negative Acceleration

C. Deceleration

D. Both B. and C.

10

32

What is the acceleration of an object that goes from 04 m/s in 4 seconds?

2 m

eter

s/se

cond2

16

met

ers/

seco

nd2

1 m

eter

/sec

ond2

0 m

eter

s/se

cond2

0% 0%0%0%

A. 2 meters/second2

B. 16 meters/second2

C. 1 meter/second2

D. 0 meters/second2

10

33

Review Questions

What do you call a stationary object that is used for a comparison to detect motion? (reference point or reference frame)

What describes how fast an object moves? (speed)

What is the type of speed when equal distances are covered in equal time? (constant speed)

What is graphed on the x-axis of a speed graph? (time)

What is graphed on the y-axis of a speed graph? (distance)

34

Review Questions

What do you call the total distance the object traveled divided by the total time it took for the object to move that distance? (average speed)

What do you call speed with direction? (velocity)

What is the formula for calculating speed? (v = d/t)

What is the formula for calculating acceleration? (a = (vf –vi)/t

What do we call the rate in change of velocity? (acceleration)

35

Review Questions

What do we graph on the y-axis of an acceleration graph?(speed)

What do we graph on the x-axis of an acceleration graph?(time)

If a person bikes 30 miles is 3 hours, what is their average speed in miles per hour?(10 miles/hour)

36

Review Questions

If a car changes its speed from 0 miles per hour to 60 miles per hour in 15 seconds, what is the car’s acceleration?(4 miles per hour per second)

37

Motion is the movement of an object in a certain distance in a certain:

0% 0%0%0%

A. Space

B. Time

C. Mass

D. Area

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38

How do you know that the car is in Motion?

0% 0%0%

A. The distance between the building and car changes.

B. The time it takes the car to move is constant.

C. The distance between the building and the car stays constant.

10

39

You’re sitting on a bus. You feel like the bus is moving backwards, but yet the bus driver assures you that you are not moving. What is the possible explanation for this feeling of movement?

You w

ere

using th

e b..

You w

ere

using th

e ...

You w

ere

using th

e ...

You w

ere

using th

e b..

0% 0%0%0%

A. You were using the bus next to you as your reference point, and that bus began moving forward.

B. You were using the windows in your bus as your reference point, and a passenger on your bus put down the windows.

C. You were using the person next to you as your reference point, and they switched seats.

D. You were using the bus driver as your reference point, and he stood up.

10

40

Joe Shmoe walks 30 meters in 10 seconds. What was his speed?

0% 0%0%0%

A. 5 meters/second

B. 3 seconds/meter

C. 3 meters/second

D. 1/3 meters/second

10

41

What is this graph showing?

0% 0%0%0%

A. A person walking at varying speeds.

B. A person walking at a constant speed and then stopping to rest.

C. A person standing still.

D. A person walked three miles.

10

42

What is the only difference between speed and velocity?

0% 0%0%0%

A. Speed is more complex while velocity is less complex.

B. Velocity is time divided by distance and speed is distance divided by time.

C. Velocity requires a direction while speed does not.

D. Speed and velocity are calculated differently.

10

43

Which of the following is an acceptable unit for velocity?

0% 0%0%0%

A. Meters/second

B. Feet per hour

C. Miles/hour South

D. Miles per hour

10

44

Which of the following is NOT an example of acceleration?

0% 0%0%0%

A. Walking in a straight line at a constant speed

B. Approaching a stop sign

C. A ball rolling down a hill

D. Turning around a corner at a constant speed

10

45

Slowing down is referred to as…

Posi

tive

Accel

erat

ion

Neg

ativ

e Acc

eler

atio

n

Dec

eler

atio

n

Both

B. a

nd C

.

0% 0%0%0%

A. Positive Acceleration

B. Negative Acceleration

C. Deceleration

D. Both B. and C.

10

46

What is the acceleration of an object that goes from 04 m/s in 4 seconds?

2 m

eter

s/se

cond2

16

met

ers/

seco

nd2

1 m

eter

/sec

ond2

0 m

eter

s/se

cond2

0% 0%0%0%

A. 2 meters/second2

B. 16 meters/second2

C. 1 meter/second2

D. 0 meters/second2

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