Question

A cloud contains spherical drops of water of radius R and charge Q. Assume the drops are far apart.

1. The electric field E0 and potential V0 at the surface of each drop is given by?

2. If two droplets happen to combine into a single larger droplet, the new potential V at the surface of the larger droplet is most nearly equal to:

Answer 1

1] Assuming the drops are far apart lets us ignore the mutual interaction between these charges.

so, using Gauss' law, the electric field at the surface of each drop is:

and Potential at the surface is:

2]

When the two droplets combine, the charge on the new droplet is doubled and the radius of the new droplet is [2]^1/3

therefore, the new potential at the surface of the larger droplet is nearly 1.578 times the potential at the surface of individual droplets.