Question

A boy goes from A to B with the velocity of 20m/min nd comes back from B to A with he velocity of 30m/min find the average velocity

Answer 1

average velocity = total displacement/total time taken



so displacement is zero
your answer is 0

Answer 2

Hey there!

1. Average speed

We know,

Speed = distance/time or s = d/t

Then,

20 = d/t1

t1 = d/20

And, 

30 = d/t2

t2 = d/30

Average speed = total distance/total time

= [2d]/[(d/20) + (d/30)]

= 24 m/s

_____________________________________________________________

2. Average velocity

As net displacement will be zero then average velocity will be also zero.

Hope It Helps You!