Easy MCQ +4 / -1 PYQ · JEE Mains 2022

A solid spherical ball is rolling on a frictionless horizontal plane surface about its axis of symmetry. The ratio of rotational kinetic energy of the ball to its total kinetic energy is

  1. A ${2 \over 5}$
  2. B ${2 \over 7}$ Correct answer
  3. C ${1 \over 5}$
  4. D ${7 \over 10}$

Solution

<p>$K{E_R} = {1 \over 2}l{w^2}$</p> <p>$= {1 \over 2} \times {2 \over 5} \times {\omega ^2} \times (m{R^2})$</p> <p>$K{E_{total}} = {1 \over 2} \times {7 \over 5} \times m{R^2} \times {\omega ^2}$</p> <p>$\therefore$ ${{K{E_R}} \over {K{E_{total}}}} = {2 \over 7}$</p>

About this question

Subject: Physics · Chapter: Rotational Motion · Topic: Centre of Mass

This question is part of PrepWiser's free JEE Main question bank. 158 more solved questions on Rotational Motion are available — start with the harder ones if your accuracy is >70%.

Drill 25 more like these. Every day. Free.

PrepWiser turns these solved questions into a daily practice loop. Chapter-wise drills, full mocks, AI doubt chat. No auto-renew.

Start free →