graphing speed making and interpreting distance – time graphs

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Graphing Speed Making and Interpreting Making and Interpreting Distance – Time Graphs Distance – Time Graphs

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Page 1: Graphing Speed Making and Interpreting Distance – Time Graphs

Graphing Speed

Making and InterpretingMaking and Interpreting

Distance – Time GraphsDistance – Time Graphs

Page 2: Graphing Speed Making and Interpreting Distance – Time Graphs

GRAPHING SPEEDDISTANCE-TIME GRAPHS

DISTANCE

TIME

Distance is plotted onthe vertical axis.

Time is plotted on the horizontal axis.

Page 3: Graphing Speed Making and Interpreting Distance – Time Graphs

CONSTANT SPEED

So…what does the term constant speed mean?

If something is “constant” what does that mean?

It does not change

Speed that does not change is constant speed.

Page 4: Graphing Speed Making and Interpreting Distance – Time Graphs

GRAPHING CONSTANT SPEEDDISTANCE-TIME GRAPHS

DISTANCE(m)

TIME (sec)

0 1 2 3 4 5

100

90

80

70

60

50

40

30

20

10

t d

1

2

3

4

5

20

40

60

80

100

Describe the shape of the line for constant speed

straightdiagonalline

Page 5: Graphing Speed Making and Interpreting Distance – Time Graphs

GRAPHING CONSTANT SPEEDDISTANCE-TIME GRAPHS

DISTANCE(m)

TIME (sec)

0 1 2 3 4 5

100

90

80

70

60

50

40

30

20

10

t d

1

2

3

4

5

20

40

60

80

100

Which object has the greatest constant speed?

A

B

C

A has the >slope thereforeit has the >constant speed.How do you know?

Page 6: Graphing Speed Making and Interpreting Distance – Time Graphs

GRAPHING AVERAGE SPEEDDISTANCE-TIME GRAPHS

DISTANCE(m)

TIME (sec)

0 1 2 3 4 5

100

90

80

70

60

50

40

30

20

10

t d

1

2

3

4

5

10

30

40

40

80

Describe the shape of the line for average speed?

zigzag

What does this part of the linemean?

A flat horizontalline meansmotion stopped.

Page 7: Graphing Speed Making and Interpreting Distance – Time Graphs

Average SpeedAverage speed is speed that changes or fluctuates.

Most moving objects travel at average speed,they start from a stand still, begin slowly, increase their speed, slow down, speed up, and eventually slow to a stop.

On a distance-time graph average speed wouldappear as a line that changes direction as it goes across the graph. It would be described asa zig-zag line.

A slanted line indicates that motion is occurring.A flat horizontal line indicates that motion hasstopped but time continues.

Page 8: Graphing Speed Making and Interpreting Distance – Time Graphs

You will recall from a previous lesson thatSpeed is calculated using the formula

s = d / tWhat is the average speed of a 18 wheelerdriver who drives non-stop 1600 miles from Houston to Los Angeles in 23 hours?

S = d / t

S = 1600 mi / 23 hrs.

S = 69.565 m/hr.

Review

Page 9: Graphing Speed Making and Interpreting Distance – Time Graphs

AccelerationIn order to understand acceleration you mustunderstand the difference in speed and velocity.

Speed is how long it takes a moving object to travel a distance.

Velocity is speed in a given direction.

NOW, ACCELERATION IS THE RATE OF CHANGEIN VELOCITY.

You must understand that if either speed ordirection changes, the object has undergoneacceleration.

Page 10: Graphing Speed Making and Interpreting Distance – Time Graphs

In this diagram, how many times will the people experience acceleration from where they are now to the end of the ride?

12

Is there anyother place that its velocity willchange?

Speeds up

Speeds up???

Slowing downis also consideredto be acceleration.

I count 6 …. Let’s look at why this might be.

Changes direction?

3

4

5

6

Page 11: Graphing Speed Making and Interpreting Distance – Time Graphs

Formula for CALCULATING ACCELERATION

acc =

final velocity - original velocitytime for change to occur

acc =Vf - Vo

tAt the top of the hill the roller coaster is moving 20 m/secand increases in speed to 40 m/sec at the bottom of thehill. It takes 4 seconds to reach the bottom of the hill.What is the roller’s coaster’s acceleration?

acc = Vf_-_Vo

t

acc =40 m/s__-__20 m/s

4 sec

acc = 5 m/s/s

Page 12: Graphing Speed Making and Interpreting Distance – Time Graphs

As it goes up the hill, it slows to 20 m/sec.The total time from the bottom of the hill to the top of the next hill is 5 seconds. What isthe acceleration of the roller coaster?

acc =

Vf__- Vo

t

acc =20 m/s_-_40 m/s

5 seconds

acc = - 4 m/s/sNotice that the answeris a negative number.This indicates that the roller coaster slows down.

Negative acceleration is also known as__________________.deceleration

Page 13: Graphing Speed Making and Interpreting Distance – Time Graphs

GRAPHING ACCELERTIONDISTANCE-TIME GRAPHS

DISTANCE(m)

TIME (sec)

0 1 2 3 4 5

100

90

80

70

60

50

40

30

20

10

t d

1

2

3

4

5

10

20

40

70

110

Describe the shape of a line showing acceleration.

Page 14: Graphing Speed Making and Interpreting Distance – Time Graphs

Graphing is something that you must learn

how to do in order to be able to pass TAKS !

Let’s check out the First Annual SHMS

Snail Race results to see if you can interpret a distance time graph.

Page 15: Graphing Speed Making and Interpreting Distance – Time Graphs
Page 16: Graphing Speed Making and Interpreting Distance – Time Graphs

INTERPRETINGDISTANCE-TIME GRAPHS

DISTANCE(in)

TIME (hr)

0 1 2 3 4 5

100

90

80

70

60

50

40

30

20

10

a

b

c

d

Pass out questionsheet for this slide.

Page 17: Graphing Speed Making and Interpreting Distance – Time Graphs

(sec)(sec) AA BB CC DD

00 00 00 00 00

11 33 22 44 .25.25

22 66 44 88 .5.5

33 99 66 1212 11

44 1212 88 1616 33

55 1515 1010 1616 66

66 1818 1212 1616 1010

77 2121 1414 1616 1515

88 2424 1616 1919 2121

99 2727 1818 2222 2828

1010 3030 2020 2525 3636

Time Total distance covered (meters)

Construct adistance –time graphfor the valuesin the datatable.

PASS OUT GRAPHPAPER FOR THISEXERCISE.

NEATNESSCOUNTS !

Page 18: Graphing Speed Making and Interpreting Distance – Time Graphs

0

5

10

15

20

25

30

35

40

0 1 2 3 4 5 6 7 8 9 10

A B C D

D I S T A N C E(m)

TIME (sec)

Your graph should look similar to this.

Page 19: Graphing Speed Making and Interpreting Distance – Time Graphs

We hope that you have been able to learn something from us.TheEnd