Two electric bulbs, one of 200 volt, 40 watt and the other 200 volt, 100 watt, are connected in a house wiring circuit.
Correct answer: C. The resistance of the filament in 40 watt bulb is more than the resistance in 100 watt bulb
- A. They have equal currents through them
- B. The resistance of the filaments in both the bulbs is same through them
- C. The resistance of the filament in 40 watt bulb is more than the resistance in 100 watt bulb
- D. The resistance of the filament in 100 watt bulb is more than the resistance in 40 watt bulb
Explanation
Since Power P = V²/R, resistance R = V²/P. Both bulbs are rated for the same voltage (200V). Therefore, the bulb with the lower power rating (40W) must have a higher resistance than the bulb with the higher power rating (100W).
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Steady current relates charge flow to potential difference, resistance and resistivity, including how temperature changes a conductor's resistance. Sources with internal resistance have terminal voltage below their emf when delivering current, and maximum power output occurs under a specific load condition rather than at zero resistance.
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