Question

A point charge Q is situated at point B on the ground. A point charge q of mass m is vertically dropped along line AB from a multi-storey building of height h. Find the position of the point charge q when it is in equilibrium.

Options

• `sqrt("qQ"/(4piepsilon_0"mg"))`

• `"Q"/"h"^2`

• `"qh"/"m"`

• None of these

Answer 1

`bb(sqrt("qQ"/(4piepsilon_0"mg")))`

Explanation:

For equilibrium

mg = F_e or mg = `"qQ"/(4piepsilon_0"y"^2)`

∴ Y = `sqrt(("qQ"/(4piepsilon_0"mg")))`