If a light bulb has half the resistance of a 50-W lightbulb,what would be its wattage? Assume both bulbs are attached to the same 120-V circuit.

Question

Quizplus · Accepted Answer

Since the resistance of the first bulb is unknown, we cannot calculate its wattage directly. However, we know that the second bulb has a resistance that is twice that of the first bulb, since resistance is inversely proportional to wattage (assuming constant voltage). Therefore, if the second bulb is rated at 50 W, the first bulb must have a wattage of 100 W, since its resistance is half that of the second bulb. Thus, the answer is D, 100 W.

If a Light Bulb Has Half the Resistance of a 50-W