- #1

in the rye

- 83

- 6

## Homework Statement

A runner covers one lap of a circular track 40.0 min diameter in 62.6 s .

## Homework Equations

If she covered the first half-lap in 28.7 s , what were her average velocity for that half-lap?

## The Attempt at a Solution

Attempt 1:

Initial Distance: 0 m

Distance of a half-lap: 20π m

Initial Time: 0 s

Final Time: 28.7 s

Displacement = Δx/Δt, where Δx = xf - x0

Displacement = (20π m - 0 m)/28.7 s = 2.19 m/s

Attempt 2:

By inspection, her total distance is aligned original position, making Δx = 0, thereby making displacement = 0.