A light bulb is rated at 100 W for a 220 V ac supply. The re... | PHYSICS - AC VOLTAGE APPLIED TO A RESISTOR | SolveeIt | Solveeit

Today, August 19

Question

A light bulb is rated at 100 W for a 220 V ac supply. The resistance of the bulb is

A

284 $\Omega$

B

384 $\Omega$

C

484 $\Omega$

D

584 $\Omega$

Answer

484 $\Omega$

Explanation

Solution

: Here, P = 100 W, $V_{rms} = 220V$

Resistance of the bulb is

$R = \frac{{V^{2}}_{rms}}{P} = \frac{(220)^{2}}{100} = 484\Omega$