A train running at a speed of 45 km/h crosses a 100 m long platform in 60 seconds. The time taken by the train to cross an electric pole is:

52 seconds

Speed = 45 km/h

= 45 × \(\frac{5}{18}\) m/sec

= 5 × \(\frac{5}{2}\) m/sec

= \(\frac{25}{2}\) m/sec 

Time = 60 seconds

Distance = Speed × Time

= \(\frac{25}{2}\) × 60

= 750

Trains length = 750 - 100

= 650

Time taken = \(\frac{650 × 2 }{ 25 }\)

= 52

The correct answer is Option (1) → 52 seconds