Correct Answer - Option 2 : 128 m
GIVEN:
Speed = 72 km/h
Length of platform = 112 m
Time to cross the platform = 12 sec
CONCEPT:
Distance traveled by a train to cross a platform is equal to the sum of lengths of the train and the platform.
FORMULA USED:
Speed = Distance/Time
CALCULATION:
Let the length of the train be x m.
Speed = 72 × 5/18 = 20 m/s
Distance = 20 × 12 = 240 m
⇒ x + 112 = 240
x = 128 m
∴ Length of the train is 128 m.
