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The power of an electric bulb is 100W. It is connected to 110V power supply. The resistance of electric bulb will be?

Correct answer: B. 121Ω

  • A. 11Ω
  • B. 121Ω
  • C. 20Ω
  • D. 200Ω

Explanation

We use the formula,P= V²/RR= V²/P = 110²/100 = 12100/100 = 121Ω

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About Current Electricity

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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