11ans. D is correct..
When the momentum of a body decreases by 10%, its Kinetic Energy (KE) decreases by
a)20%
b)40%
c)36%
d)none of these
FULL DESCRIPTION REQUIRED. NO SHORT ASNWER
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4 Answers
1057first of all we have to see that the dec in momentum is only due dec in velocity(mass is constant)
let mass be m nd original vel be v
v' be the changed velocity
mv=x
mv'=9x10
so vv'=910
% dec in KE=12mv2 -12mv'212mv2 into 100
12 and m get cancelled
we are left with v2-v'2v2 into 100
so the answer turns out be 102 -92102 into 100
which is 19%
