(b) A train of length 120 m is travelling at 144km/h.
It passes under a bridge of width 20m.
Find the time taken for the whole train to pass under the bridge.
Give your answer in seconds.

Respuesta :

Answer:

3 seconds.

Step-by-step explanation:

First calculate the time for each 20m length to pass through the bridge.

The train takes 3600 seconds to travel 144,000 m

So it takes 3600/144000 seconds to travel 1m.

and 3600 * 20 / 144000 seconds to travel 20 m.

As the train is 120 m long  and there are 6 * 20 m in 120m the answer is:

3600 * 20 * 6 / 144000 seconds.

= 3 seconds.