Question

A train 800m long is running at a speed of 78 km/hr. If it crosses a tunnel in 1 minute, then the length of the tunnel is

• A. 7200 m
• B. 500 m
• C. 1300 m
• D. 1480 m

Answer 1

Answer:

B. 500 m

let length of tunnel be x m speed=78km/hr = 65/3m/s 65/3 = (800+x) /60=(800+x)3=65 * 60 800 + x = 65 * 20 x = 1300-800=500