Question

In how much time will a train cross a tunnel that is 5 times the length of the train, given that the train crosses a standing man on the platform in 8 seconds.
1. 20 seconds
2. 30 seconds
3. 48 seconds
4. 40 seconds

Answer 1

Correct Answer - Option 3 : 48 seconds

Given:

The train crosses a standing man on the platform in 8 seconds

Concept Used:

Time taken by train to cross a pole/standing man/a point = Time taken by train to cross its own length

[∵ length of standing man = 0]

Time taken by a train to cross a platform = Time taken to cross (the length of the platform + the length of train)

Calculation:

Time taken by train to cross standing man = 8 seconds = Time taken by train to cross its own length

Now, length of the tunnel is 5 times the length of the train

⇒ The train has to cover its own length + the length of the tunnel

Time taken by train to cover the tunnel= (5 + 1) × Time taken by train to cross its own length

= 6 × 8 seconds

= 48 seconds