Question

A traln travelling @ speed of 72 kmph takes 24 sec to cross a vertical pole. How
much time will the same train, travelling at a speed of 36 kmph take to cross a
platform of length 320 meter ? (in seconds)​

Answer 1

Step-by-step explanation:

Let the length of the train be l meters. The speed of the train is 72 kmph. Now 72kmph=72000mph

=72000/3600=20mps. The combined length of platform and train is (l+120)m. The time taken to cross the platform by the train is 23 secs, which can be expressed as:(l+120)/20=23. So the length ofthe train is,l=23×20-120=460-120=340 m. The time taken by the train to cross the pole is t(say) & it equals to [(length of the train)/speed of the train].

t=l/20=340/20=17