Question

A mass 'M' is moving with a constant velocity parallel to X-axis. Angular momentum with respect to the origin:

• A. goes on decreasing continuously
• B. remains constant
• C. is zero
• D. goes on increasing continuously

Answer 1

The correct option is B remains constant

Given,

$M=$mass

The angular momentum with respect to the origin,

$\overrightarrow{L}=\overrightarrow{r}\times M\overrightarrow{v}$

$\overrightarrow{L}=m(\overrightarrow{r}\times \overrightarrow{v})$

at any time angle between $\overrightarrow{r}$ and $\overrightarrow{v}$ is ${90}^0$ and $|\overrightarrow{r}|=h$

The angular momentum is,

$|L|=m|\overrightarrow{v}||\overrightarrow{r}|sin{90}^0=mvh$

The angular momentum remains constant.

The correct option is B.