Q. A train running at a speed of 90 km/h crosses a 500-metre-long platform in 36 seconds. What is the length of the train ?

(A) 350 metres  (B) 400 metres  (C) 450 metres  (D) 500 metres

Solution:

Speed = 90 km/h

90 × 1000/3600 = 25 m/s 

Time = 36 seconds

Total Distance = 25 × 36 = 900 m 

When a train crosses a platform:

Total Distance = Train Length + Platform Length 

Therefore,

Train Length = 900 − 500 = 400 m

Ans: (B) 400 metres

Shortcut Formula: Train Length = (Speed × Time) − Platform Length