1. Tardigrade
  2. Question
  3. Physics
  4. A body rolls down an inclined plane. If its kinetic energy of rotation is 40 % of its kinetic energy of translation motion, then the body is

Question Error Report

Thank you for reporting, we will resolve it shortly

Back to Question

Q. A body rolls down an inclined plane. If its kinetic energy of rotation is $40\%$ of its kinetic energy of translation motion, then the body is

KEAMKEAM 2015System of Particles and Rotational Motion

Solution:

The ratio of kinetic energies
$\frac{ KE _{ rot }}{ KE _{\text {trans }}}=\frac{\frac{1}{2} m v^{2}\left(\frac{K^{2}}{R^{2}}\right)}{\frac{1}{2} m v^{2}} =\frac{K^{2}}{R^{2}}=0.4=\frac{2}{5}$
$\Rightarrow K^{2} =\frac{2}{5} R^{2}$
$\Rightarrow m K^{2}=\frac{2}{5} m R^{2}$
$\Rightarrow $ Body is a solid sphere