Question

The resistance of a bulb fitted in a house varies inversely as its

• A. power
• B. potential drop
• C. current
• D. none of these

Answer 1

The correct option is A

power

1. When current is constant in any circuit the relation between resistance and power are given by, $P=I^{2}R$, where power is directly proportional to resistance.
2. When the potential difference is constant in any circuit the relation between resistance and power is given by, $P=\frac{V^2}{R}$, where power is inversely proportional to resistance.

In our houses, a parallel combination is used such that the potential deference is constant, so the relation between resistance and power is inversely proportional.

Hence, option A is correct.