Question

a 120 M long train is moving in a direction with speed 20 metre per second .a train B moving with 30 metre per second in the opposite direction and 130 metre long crosses the first train in a time

Answer 1

The relative speed for approaching bodies is the sum of their speeds.

The relative speed is thus :

20 + 30= 50m/s

The relative distance covered is :

130m + 120 m = 250 m

Time = Distance / speed

Time = 250/50 = 5 seconds

Time is therefore 5 seconds
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