Announcements

• The next make-up lab will allow students to make up any lab from the first semester

• No homework due Friday

MOST MISSED QUESTIONS

Kinematics Graphing

Tortoise and the Hare

• Video

Practice: Tortoise and the Hare

Questions (use evidence from the graph)1. What was the length of the race?2. What was the hare doing from 6 min until 71

minutes? How do you know?3. How much time did the Hare sleep for? At what

position was he sleeping?4. Who was traveling faster in the beginning of the

race? Cite specific evidence from the graph. 5. When the hare went for sleep, what was the

position of the tortoise? What was the position of the hare at this time?

6. At what time did the tortoise cross over the hare?7. When the tortoise reached the destination, where

was the hare?

Check for understanding

• Which object is traveling faster?• Which object starts off ahead?

POSITION-TIME GRAPHS, DISPLACEMENT-TIME GRAPHS,AND DISTANCE-TIME GRAPHS

Distance vs. Time GraphsDuring what time interval was the object NOT MOVING?

Distance vs. Time

024681012141618

0 1 2 3 4 5 6 7

Time (s)

Dista

nce (

m)

2 – 3 secondsThe interval on the graph wherethe distance remains constant!

Displacement vs. Time Graphs

Displacement vs. Time

-4-3-2-10123456

0 1 2 3 4 5 6 7

Time (s)

Disp

lacem

ent (

m)

When the displacement isnegative, the object has a

position to the left of the origin1 – 2 and 4 – 5 seconds

Constant displacement means thatthe object doesn�t move

The object�s final position isat +1 meter (1 meter to the

right of the origin)

During what time interval(s) was the object to the left of the origin?During what time interval(s) was the object NOT MOVING?At what distance from the origin does the object stop?

How Graphs Show Velocity and Speed

Position vs. Time

Time

Posi

tion

What is happening in thisgraph?

MotionlessObjectCONSTANT

ZEROSLOPE

How Graphs Show Velocity and Speed

What is happening in thisgraph?

Position vs. Time

Time

Posi

tion

CONSTANTPOSITIVE

SLOPE

Moving withCONSTANT

positive velocity

How Graphs Show Velocity and Speed

What is happening in thisgraph?

Position vs. Time

Time

Posi

tion

INCREASINGSLOPE

Moving withINCREASING

velocity

HOW TO BE A GRAPHING DVA

DiVAGraphing DiVA

Displacement/Distance

Velocity/Speed

Acceleration

Slop

e Area

15 m/s 2.5 m/s/s

Displacement

Question 2 - 10

Answer 2 – 10

• Constant non-zero acceleration• 1. Quadratic

Question 2 - 20

Answer 2 – 20

• Constant acceleration of 9/8 m/s/s

• 4. Constant slope of zero

Question 2 - 30

Answer 2 – 30

• 8. 1) Both demonstrate positive acceleration

Question 2 - 40

Answer 2 – 40

• 1. 0.0 m/s/s

Question 2 - 50

Answer 2 – 50

• 3. 40m (area under the curve/integral)