Question

The total energy of the harmonic oscillation of mass $2\text{kg}$ is $8\text{J}$. If its potential energy at mean position is $6\text{J}$, its kinetic energy at the mean position will be

• A. $8\text{J}$
• B. $6\text{J}$
• C. $2\text{J}$
• D. $14\text{J}$

Answer 1

The correct option is C $2\text{J}$

Given,
Total energy $\left(E\right)=8\text{J}$
Potential energy at mean position $\left(U\right)=6\text{J}$
We know that, at mean position $\text{PE}$ is minimum.
$\therefore \text{KE}$ is maximum at mean position.$\Rightarrow K_{max}+U_{min}=E$(as total energy remains conserved in SHM)
$K_{max}=E-U_{min}=8-6=2\text{J}$