1.  A train 360 m long is running at a speed of 45 km/hr. In what time will it pass a bridge 140 m long?
A. 40 sec
B. 42 sec
C. 45 sec
D. 48 sec

Answer: Option A

Explanation:

Formula for converting from km/hr to m/s:

  X km/hr = X x 5 m/s.
18

Therefore, Speed = 45 x 5 m/sec = 25 m/sec.
18 2

Total distance to be covered = (360 + 140) m

= 500 m.

Formula for finding Time = Distance
Speed

Required time = 500 x 2 sec = 40 sec.
25