Correct Answer - Option 1 : 13 seconds
Given:
Speed of train = 108 km/h
T = 6 seconds
L of platform = 210 m
Formula used:
Speed = Distance/Time
m/s = 5/18 km/hr
Calculation:
Converting speed of train from km/h to m/s = 108 × 5/18
⇒ speed = 30 m/s
⇒ Length of train = 30 × 6
⇒ Length of train = 180 m
⇒ Time taken to cross platform of 210 m = (210 + 180)/30
⇒ Time taken to cross platform of 390 m = 13 seconds
∴ time taken to cross platform of 210 m is 13 seconds