Question

A train S,120 m long runs with a velocity 72 kmh^–1; while train T, 130 m long is running in opposite direction with a velocity 108 kmh^–1. The time taken by T to cross train S is 

(a) 5 sec 

(b) 10 sec 

(c) 25 sec 

(d) 50 sec

Answer 1

Correct option  (a) 5 sec 

Explanation:

Velocity of S - train = 20 ms^–1 

Velocity of T - train = –30 ms^–1 

Relative vel. of T w.r.t. s