Question

A body goes from A to B with a speed of 20m/s and comes back from B to A with a speed of 30m/s . Find the a) average speed and b) average velocity.

Answer 1

hello !
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a) Average speed = 2V1V2/V1+V2 = 1200/50 = 24 m/s

B) Average Velocity = 0 as displacement = 0 
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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

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

Hope It Helps You!