Question

A body covers half its journey in 40m/s and the other half with a speed of 60m/s . What is the average speed during the whole journey?

Answer 1

Let the total distance it covers be 2x

Time taken to cover the first half of distance t1= x/40

Time taken to cover the next half of distance t2= x/60

Total time taken = t1 + t2

= x/40 + x/60

= 100x/2400

=x/24

Average speed = total distance/total time taken

= 2x/(x/24)

= 48x/x ms-1

= 48 m/s

Hope it helps...