Question

A train rolls past a stationary observer. To him, the train is moving at a speed of 23 m/s west, and a woman on the train is moving at a speed of 22.4 m/s west. How long does it take the woman to move 13 m relative to the train?

Answer 1

Woman's velocity relative to train (23 m/s - 22.4 m/s) = 0.6 m/s
Distance woman wants to travel = 13m
To find how long she will take to move 13m relative to the train, take the distance she wants to travel divided by her velocity relative to the train.

(13m)/(0.6 m/s) = 21.6667 seconds or 21.7 seconds. 

Therefore, it will take the woman 21.7 seconds to move 13m.