Q. A body moving with velocity v has momentum and kinetic energy numerically equal. What is the value of v?
A) $2ms^{- 1}$
B) $\sqrt{2}ms^{- 1}$
C) $1ms^{- 1}$
D) $0.2ms^{- 1}$
Explanation
(a) Kinetic energy is the energy possessed by a body due to its velocity(v)given by
$K = \frac{1}{2}mv^{2}\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ldots(i)$
Momentum(P)=$m \times v\ \ \ \ldots(ii)$
Given, $K = p$
$\therefore\ \frac{1}{2}mv^{2} = mv\ \ or\ \ v = 2ms^{- 1}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.