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A body falling with a speed of 2 ms-stri...

A body falling with a speed of 2 ms-strikes the floor and rebounds with a speed of 1 ms. The loss of energy is:

A

0.125

B

0.25

C

0.4

D

0.75

Text Solution

Verified by Experts

The correct Answer is:
d
Here, loss in K.E.=`1/2m[v_1^2-v_2^2]`
=`1/2m[(2)^2-1^2]=3/2m`.
Initial energy=`1/2mxx(2)^2=2m`
% age loss=`(3/2m)/(2m)xx100=75%`
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