Question

Two train each 500 m long, are running in opposite directions on parallel tracks. if their speeds are 45 km/hr. and 30 km/hr. respectively, the time taken by the slower train to pass the driver of the faster one is

Answer 1

Relative speed == (45 + 30) km/hr=75 x5m/sec18=125m/sec.6

We have to find the time taken by the slower train to pass the DRIVER of the faster train and not the complete train.

So, distance covered = Length of the slower train.

Therefore, Distance covered = 500 m.

 Required time =500 x6= 24 sec.125

Answer 2

relative speed = 45+30= 75km/hr 
                     in seconds= 75x5/18 =  125/6 seconds 
 distance covered = Length of the slower train.
                             = 500m 
  Required time =500/125×6 = 24 seconds
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