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Two positive ions each have charge q and are a distance d apart. If the repulsive force between them is F, then the number of electrons absent from each ion, taking e as the charge of one electron, is

1. 4πϵ0 Fd²/e²
2. √(4πϵ0 Fe²/d²)
3. √(4πϵ0 Fd²/e²)
4. 4πϵ0 Fd²/q²

Correct answer: √(4πϵ0 Fd²/e²)

Solution

The correct option relates the repulsive force between two positive ions to the number of electrons missing from each ion by using Coulomb's law. The formula shows that the force is proportional to the product of the charges (which are related to the number of missing electrons) and inversely proportional to the square of the distance between them, allowing us to derive the number of electrons in terms of the given variables.

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