A cyclist is riding towards a stationary vertical plane mirror at a constant speed of 5m s−1. When he is 60m away from the mirror, the head-lamp on his helmet emits a brief flash of light directed exactly along the normal to the mirror.
(i) Find the time taken for the flash to return to the cyclist after reflection.
(ii) How far does the cyclist move during this interval?
(iii) What is the separation between the cyclist and the mirror at the instant the flash returns?