Answer to Question #233827 in Physics for Sean

Question

For his daily training, an athlete runs around a 15 m radius track five times in 2.5 minutes. What is his average speed in m/s?

Answer 1

Given:

$R=15\:\rm m$

$t=2.5\:\rm min=150\;\rm s$

$n=5$

The period of rotation

$$T=\frac{t}{N}=\frac{150\:\rm s}{5}=30\: \rm s$$

The average speed

$$v=\frac{2\pi R}{T}=\frac{6.28*15\;\rm m}{30\:\rm s}=19\:\rm m/s$$