Question

A runner covers one lap of a circular track 40.0 in diameter in 63.3 .

For that lap, what was her average velocity?

If she covered the first half-lap in 28.6 , what were her average velocity for that half-lap?

Answer 1

Her avg velocity is zero because her total displacement is zero around any closed path. This is because velocity is a vector quantity that depends on direction. Her average speed is non-zero, depending only on the distance she ran divided by the time. (Distance is a scalar quantity so direction doesn't matter.)