Question

A train crosses a pole in 5 seconds and crosses the tunnel in 20 seconds. If the speed of the train 90 m/s, then find the length of the tunnel.

• A. 1350 m
• B. 900 m
• C. 1200 m
• D. 800 m

Answer 1

Answer:

A. 1350 m

Let the length of the tunnel be x m and the length of the train be y m 5 = (y/90) y = 450 m Time to crosses the tunnel = Distance/Speed 20 = (y + x)/90 ⇒ 20 × 90 = (450 + x) ⇒ x = 1800 - 450 = 1350