# A particle is moving in a circle of radius $\mathrm{r}$ under the action of a force $\mathrm{F}=\alpha \mathrm{r}^{2}$ which is directed towards centre of the circle. Total mechanical energy (kinetic energy + potential energy) of the particle is (take potential energy $=0$ for $\mathrm{r}=0$ ) :

Question:

A particle is moving in a circle of radius $\mathrm{r}$ under the action of a force $\mathrm{F}=\alpha \mathrm{r}^{2}$ which is directed towards centre of the circle. Total mechanical energy (kinetic energy + potential energy) of the particle is (take potential energy $=0$ for $\mathrm{r}=0$ ) :

1. $\frac{1}{2} \alpha r^{3}$$2.$\frac{5}{6} \alpha \mathrm{r}^{3}$3.$\frac{4}{3} \alpha r^{3}$4.$\alpha \mathrm{r}^{3}

JEE Main Previous Year Single Correct Question of JEE Main from Physics Work, Energy and Power chapter.

JEE Main Previous Year April 11, 2015

Correct Option: 2

Solution:

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