Question

380 metre long train moving with an average speed of 162 km/h crosses a platform in 16 seconds. a man crosses the same platform in 17 seconds. what is the speed of the man?

Answer 1

First convert 162km/h to m/s. i.e. 45m/s.

Train crosses the platform means that the whole length of train crosses the platform which means the total length train traveled is length of train + platform. Let say 380+ x metres

Time taken is 16 second. Thus applying speed×time,

380+ x = 45×16

380 + x = 720

x = 340 metres . Thus, length of platform is 340 m

The man takes 17 sec to cross the platform. let speed of man is y

So, 340 = 17 × y

y = 20 m/s

Thus speed of man is 20 m/s. When converted to km/h, you get speed of man as 72 km/h.