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Electric potential at a point 'P' due to a point charge of 5 × 10^-9 C is 50 V. The distance of 'P' from the point charge is : (Assume, 1/(4πϵ0) = 9 × 10^9 Nm^2C^-2)

1. 9 cm
2. 3 cm
3. 0.9 cm
4. 90 cm

Correct answer: 90 cm

Solution

The electric potential (V) due to a point charge (Q) is given by the formula V = k * Q / r, where k is the electrostatic constant. Rearranging this formula to solve for distance (r) and substituting the given values shows that the distance from the charge to point P is 90 cm.

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