Question

A train covers half of its journey with a speed of 30 m/s and the other half with a speed of 40 m/s. calculate the average speed of the train during the whole journey.

Answer 1

When journey is travelled in equal distances but different speeds then average speed is shown by-

n/average speed=1/v₁+1/v₂+1/v₃...and so on

Where n=no of equal distance intervals.

Here,

2/v=1/30+1/40

v=120*2/7

=34.2 m/s