Question

if the moment of an object is increased by 10% , then its kinetic energy will increase by
a) 20% b) 21% c) 40% d) 19%

Answer 1

given:-
velocity of the object - v
mass- m
than, momentum - mv
initial kinetic energy- mv^2\2.
new momentum- mv+10%of mv
= 11mv\10
=mv (11v /10).
than ,new velocity= 11v\10.
than, change in velocity= v\10.
% increase in k.E = m(11v\10)^2/2
= 21%.