An electric bulb is rated at 220 V, 100 W. What is its resistance?
Correct answer: D. 484 Ohms
- A. 250 Ohms
- B. 350 Ohms
- C. 450 Ohms
- D. 484 Ohms
Explanation
In this case, we are given the voltage (V) of the bulb, which is 220 V, and the power P of the bulb, which is 100W. We can use the formula for:Power (P) = V2 / RR = V2 / P= (220)2/ 100= 22 x 22= 484 Ohms
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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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