Physics · Rotational Dynamics

JEE Main 2025 — 4 April, Morning Shift — Question 54

If $\vec{L}$ and $\vec{P}$ represent the angular momentum and linear momentum respectively of a

particle of mass ' $m$ ' having position vector as $\vec{r}=a(\hat{i} \cos \omega t+\hat{j} \sin \omega t)$ .

The direction of force is

Answer: B

$\vec{r}=a \cos \omega t \hat{i}+a \sin \omega t \hat{j}$

$\vec{v}=\frac{d \vec{r}}{d t}=-a \omega \sin \omega t \hat{i}+a \omega \cos \omega t \hat{j}$

$\vec{a}=\frac{d \vec{v}}{d t}=-a \omega^{2} \cos \omega t \hat{i}-a \omega^{2} \sin (\omega t) \hat{j}$ $\vec{F}=m \vec{a}$

$\vec{a}$ is antiparallel to $\vec{r}$

Answer key and solution verified before publishing.

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