A particle of mass $\mathrm{m}$ is rotating in a plane in circular path of radius $\mathrm{r}$. Its angular momentum is $\mathrm{L}$. The centripetal force acting on the particle is.A) $\frac{\mathrm{L}^{2}}{\mathrm{mr}}$B) $\frac{\mathrm{L}^{2} \mathrm{~m}}{\mathrm{r}}$C) $\frac{\mathrm{L}^{2}}{\mathrm{~m}^{2} \mathrm{r}^{2}}$D) $\frac{\mathrm{L}^{2}}{\mathrm{mr}^{3}}$

Home » A particle of mass is rotating in a plane in circular path of radius . Its angular momentum is . The centripetal force acting on the particle is.A) B) C) D)

A particle of mass $\mathrm{m}$ is rotating in a plane in circular path of radius $\mathrm{r}$ . Its angular momentum is $\mathrm{L}$ . The centripetal force acting on the particle is.
A) $\frac{\mathrm{L}^{2}}{\mathrm{mr}}$
B) $\frac{\mathrm{L}^{2} \mathrm{~m}}{\mathrm{r}}$
C) $\frac{\mathrm{L}^{2}}{\mathrm{~m}^{2} \mathrm{r}^{2}}$
D) $\frac{\mathrm{L}^{2}}{\mathrm{mr}^{3}}$

Physics

A particle of mass $\mathrm{m}$ is rotating in a plane in circular path of radius $\mathrm{r}$ . Its angular momentum is $\mathrm{L}$ . The centripetal force acting on the particle is.
A) $\frac{\mathrm{L}^{2}}{\mathrm{mr}}$
B) $\frac{\mathrm{L}^{2} \mathrm{~m}}{\mathrm{r}}$
C) $\frac{\mathrm{L}^{2}}{\mathrm{~m}^{2} \mathrm{r}^{2}}$
D) $\frac{\mathrm{L}^{2}}{\mathrm{mr}^{3}}$

Correct option is D) $\frac{\mathrm{L}^{2}}{\mathrm{mr}^{3}}$
Centripetal force, $F=\frac{\mathrm{mv}^{2}}{\mathrm{r}}=\frac{\mathrm{m}}{\mathrm{r}} \frac{\mathrm{L}^{2}}{\mathrm{~m}^{2} \mathrm{r}^{2}}=\frac{\mathrm{L}^{2}}{\mathrm{mr}^{3}}$
$\left[\mathrm{As}, \mathrm{L}=\mathrm{mvr} \therefore \mathrm{v}=\frac{\mathrm{L}}{\mathrm{mr}}\right]$

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