A train 820 m long is running at a speed of 78 km/hr. If it crosses a tunnel in 1 min, then the length of the tunnel is?
Options
A) 510	B) 540	C) 480	D) 520	E) 589
Speed = 78 * 5/18 = 65/3 m/sec.   Time = 1 min = 60 sec.   Let the length of the train be x meters.   Then, (820 + x)/60 = 65/3   x = 480 m.   Answer: Option 480
<result>C</result>
A train 820 m long is running at a speed of 78 km/hr. If it crosses a tunnel in 1 min, then the length of the tunnel is?