Q149 / 200 · WBJEE 2014 · Physics
When a particle executing SHM oscillates with a frequency $v$, then the kinetic energy of the particle
- Achanges periodically with a frequency of $v$
- Correct answerBchanges periodically with a frequency of $2 \mathrm{v}$
- Cchanges periodically with a frequency of $\mathrm{v} / 2$
- Dremains constant
Solution
We know that
Kinetic energy $K=\frac{1}{2} m u^{2}$
where $u=\frac{d y}{d t}=\omega a \cos \omega t$
So. $K=\frac{1}{2} m \omega^{2} a^{2} \cos ^{2} \omega t$
Hence, kinetic energy varies periodically with double the frequency of SHM. So, when a particle executing SHM oscillates with a frequency v, then the kinetic energy of particle changes periodically with a frequency of $2 v$.
Hence, the correct answer is option: 'B'.