# A small particle of mass $m$ is projected at an angle $\theta$ with the $x$-axis with an initial velocity $v_{0}$ in the $x$-y plane as shown in the figure. At a time $t<\frac{v_{0} \sin \theta}{g}$, the angular momentum of the particle iswhere $\hat{i}, \hat{j}$ and $\hat{k}$ are unit vectors along $x, y$ and $z$-axis respectively.

Question:

A small particle of mass $m$ is projected at an angle $\theta$ with the $x$-axis with an initial velocity $v_{0}$ in the $x$-y plane as shown in the figure. At a time $t<\frac{v_{0} \sin \theta}{g}$, the angular momentum of the particle is

where $\hat{i}, \hat{j}$ and $\hat{k}$ are unit vectors along $x, y$ and $z$-axis respectively.

1. $-m g v_{0} t^{2} \cos \theta \hat{j}$

2. $m g v_{0} t \cos \theta \hat{k}$

3. $-\frac{1}{2} m g v_{0} t^{2} \cos \theta \hat{k}$

4. $\frac{1}{2} m g v_{0} t^{2} \cos \theta \hat{i}$

JEE Main Previous Year Single Correct Question of JEE Main from Physics System of Particles and Rotational Motion chapter.

JEE Main Previous Year 2010

Correct Option: 3

Solution:

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