Question

an electric bulb of 100w at 220v is connected to A 220v line. Find the current through the line and resistance of the lamp​

Answer 1

Answer:

Assuming the lamp wattage for the lamp is based on 220V being supplied to it, then the bulb resistance (when dissipating 100W of power) is R = V^2/P = 220^2/100 = 484Ω. Thus the current that the lamp will draw will be I =- V/484. Assuming the applied voltage is 220V, then I = 220/484 = 0.45A.