Q114 / 180 · NEET 2013 (Karnataka) · Physics
A particle of mass $m$ oscillates along $x$-axis according to equation $x=a$ sin $\omega t$. The nature of the graph between momentum and displacement of the particle is:
- ACircle
- BHyperbola
- Correct answerCEllipse
- DStraight line passing through origin
Solution
According to the question
$$
x=\operatorname{arsin} \omega t \rightarrow \frac{x}{a}=\sin \omega t
$$
Now velocity $\mathrm{V}=\frac{d x}{d t}=a \omega \cos \omega t$ $\Rightarrow \quad \frac{\mathrm{V}}{a \omega}=\cos \omega t$
From eq. (i) and (ii)
$$
\begin{gathered}
\frac{x^2}{a^2}+\frac{v^2}{a^2 \omega^2}=\sin ^2 \omega t+\cos ^2 \omega t \\
\frac{x^2}{a^2}+\frac{v^2}{a^2 \omega^2}=1
\end{gathered}
$$
$\Rightarrow$ This is the equation of ellipse. So the graph between moment and displacement of particle is ellipse.
Hence, the correct answer is option: 'C'.