Two trains are moving in the opposite directions on parallel tracks, one with a velocity twice that of other. If the total length of the two trains is 480 ft and they take 3 seconds to cross each other, find their individual velocities.

Asked by Topperlearning User | 4th Jun, 2014, 01:23: PM

Expert Answer:

Let the two trains A and B be moving in opposite directions with with velocities u ans 2u respectively.

Relative velocity V = u + 2u = 3u

Total distance moved = total length of the two trains S = 480 ft.

time taken by the trains to cross each other t = 3 seconds

Now, S = Vt

or, 480 = 3u x 3

or, u = 53.33 ft/s

and 2u = 106.66 ft/s

Answered by  | 4th Jun, 2014, 03:23: PM