Question

A body moves half of distance with velocity V1 and another half of distance with velocity V2 then Average velocity =?​

Answer 1

Assume that the distance covered by the body is x km.

Given that, body moves half of distance with velocity V1 and another half of distance with velocity V2.

Now,

Average speed is defined as the total distance covered by total time taken. Whereas, average velocity is defined as the total displacement with respect to total time taken.

Since, in first half the body covers the distance of x. Similarly, in second half body covers the distance of x.

Therefore, the total distance covered by the body is twice of the distance i.e. 2x km.

Also,

Time = Distance/Speed

For first half:

t1 = x/V1

For second half:

t2 = x/V2

Total time taken = t1 + t2

= x/V1 + x/V2

= (V2*x + V1*x)/V1V2

Average velocity = 2x/[(V2*x + V1*x)/V1V2]

= 2(V1V2)/(V1 + V2)