How to Calculate Average Velocity on a Circular Track?

[cvc121]

Homework Statement

A car travels on a circular track at 20m/s. The track has a circumference of 2.0km. What is the average velocity of the car over one lap?

Homework Equations

The Attempt at a Solution

Since the car is traveling at a constant speed of 20m/s, wouldn't the average velocity be 20m/s? The answer key says 0.

 

[PietKuip]

Cannot you imagine why 0 is a valid answer?

 

[gneill]

Check the definitions of average velocity and average speed.

 

[cvc121]

Oh, my bad. Since the car arrives back at the same location, there is no change in displacement and thus, average velocity is 0.

 

[gneill]

Oh, my bad. Since the car arrives back at the same location, there is no change in displacement and thus, average velocity is 0.

Yessir!