Objective SWBAT use distancetime graphs to determine an

Objective • SWBAT use distance-time graphs to determine an object’s speed.

“Service to others is the rent you pay for your room here on Earth. ” —Muhammad Ali

Distance-Time Graph

Velocity • Velocity is speed in a specific direction. – When moving forward, velocity is positive. – When moving backward, velocity is negative.

Interpreting Distance-Time Graphs • From point A to point B… – Distance traveled = 8 m – 0 m = 8 m – Time = 4 s – 0 s = 4 s Object is moving forward at constant speed of 2 m/s

Interpreting Distance-Time Graphs • From point B to point C… –d=8 m– 8 m=0 m –t=7 s– 4 s=3 s Object is not moving.

Interpreting Distance-Time Graphs • From point C to point D… –d=0 m– 8 m=— 8 m – t = 10 s – 7 s = 3 s Object is moving backwards.

Note! • The slope of a line segment = speed of the object during that time.

Check For Understanding • When the line on a distance-time graph has a negative slope, the object is… A. Moving forward. B. Moving backward. C. Not moving.

1. What was the speed from 0 seconds to 5 seconds? 2. During which time interval was this person moving the fastest? 3. During which time interval was this person not moving?

Check For Understanding • When the line on a distance-time graph is flat, the object is… A. Moving forward. B. Moving backward. C. Not moving.

1. What is Student A’s speed? 2. What is Student B’s speed? 3. Who is moving faster?

Check For Understanding • When the line on a distance-time graph has a positive slope, the object is… A. Moving forward. B. Moving backward. C. Not moving.

Challenge Question • Are either of these students ever accelerating? How can you tell?

Challenge Question • No. The slope of each line does not change, so their speeds are staying the same the entire time. The speeds do not increase or decrease.

What acceleration would look like…