Question

The kinetic energy of a body of mass 2 kg and momentum 2 Ns is

• A. 1 J
• B. 2 J
• C. 3 J
• D. 4 J

Answer 1

The correct option is A 1 J

Given:mass(m)$=2kg$, momentum(p)$=2Ns$
we know; $p=mv$

$v=\frac{p}{m}$

$v=1m{s}^{-1}$

Kinetic energy (K.E) $=\frac{1}{2}m{v}^2$,

$K.E=\frac{1}{2}pv$

$K.E=\frac{1}{2}\times 2\times 1$

$K.E=1J$