Two positive ions, each carrying a charge q, are separated by a distance d. If F is the force of repulsion between the ions, the number of electrons missing from each ion will be ( e being the charge of an electron)

Options

(a) 4π?￢ﾂﾀFd² / e²
(b) √(4π?￢ﾂﾀFe² / d²)
(c) √(4π?￢ﾂﾀFd² / e²)
(d) 4π?￢ﾂﾀFd² / q²

Correct Answer:

√(4π?￢ﾂﾀFd² / e²)

Explanation:

Let ne be the no. of electrons missing.
F = 1 / 4π?￢ﾂﾀ . q² / d²
q = √(4π?￢ﾂﾀd²F) = ne
n = √(4π?￢ﾂﾀFd² / e²)