Question

Question: A solid plastic sphere of radius R has charge -Q distributed uniformly over its surface. It is far from all other objects.

(a). Sketch the molecular polarization in the interior of the sphere and explain briefly.

(b). Calculate the potential relative to infinity at the center of the sphere.

Short answer

(a). The required sketch is:

(b). The required potential is $V_c=\frac{-kQ}{R}$.

Step-by-step solution

Electric field

The electric field is that field that is the area around the charged object where the effect of the electric force can be experienced and the magnitude of which decreases with an increase in the distance of the charged object.

Part (a)

It is given that there is a solid sphere around which the negative charge Q is spread over its surface.

Then the diagram for the charged distribution would be:

Part (b)

It is known that the potential relative to the infinity at the center of the sphere is directly proportional to the charge and inversely proportional to resistance.

Then the expression will be,

$V_c=\frac{-kQ}{R}$

Where the negative sign implies that the charge spread over the surface is negative.