Assertion (A): The work done by the electrost | vedclass

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(A) The work done $W$ by a force $\vec{F}$ over a displacement $d\vec{r}$ is given by the dot product: $W = \int \vec{F} \cdot d\vec{r}$. When a point

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Both Assertion and Reason are true and Reason is the correct explanation of Assertion.

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(A) The work done $W$ by a force $\vec{F}$ over a displacement $d\vec{r}$ is given by the dot product: $W = \int \vec{F} \cdot d\vec{r}$. When a point charge moves in a circular path around another charge,the electrostatic force is always directed radially (towards or away from the center),while the displacement vector is always tangential to the circular path. Since the angle between the radial force and the tangential displacement is $90^{\circ}$,the dot product $\vec{F} \cdot d\vec{r} = F dr \cos 90^{\circ} = 0$. Thus,the work done is zero. Both the assertion and the reason are true,and the reason correctly explains why the work done is zero.

Assertion $(A)$: The work done by the electrostatic force is zero when a point charge moves in a circular path around another charge.
Reason $(R)$: The dot product of force and displacement vectors gives work done.

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Assertion $(A)$: The work done by the electrostatic force is zero when a point charge moves in a circular path around another charge. Reason $(R)$: The dot product of force and displacement vectors gives work done.