Show what change of kinetic energy of a body will be observed when:
(1)its mass is doubled.
(2) its velocity is doubled.

Question

Show what change of kinetic energy of a body will be observed
when:
(1)its mass is doubled
(2) its velocity is doubled

Prince Kumar · Accepted Answer

Solution:- (i) Let the initial mass be m.

Final mass of the body is, m' = 2m,

$K . E = \frac{1}{2} m v^{2} .... (i) K . E' = \frac{1}{2} m' v^{2} = \frac{1}{2} (2 m) v^{2} = 2 K . E$

(ii) Let he initial velocity of the body be v.

Final velocity of the body is, v' = 2v

$K . E = \frac{1}{2} m v^{2} .... (i) K . E' = \frac{1}{2} m {v'}^{2} = \frac{1}{2} m {(2 v)}^{2} = 4 \times \frac{1}{2} m v^{2} = 4 K . E .$