A heater coil is cut into two equal parts, and only one part is now used in the heater. The heat generated will now be:
Correct answer: D. Doubled
- A. Halved
- B. Four times
- C. One-fourth
- D. Doubled
Explanation
When the coil is cut in half, its resistance is halved (R' = R/2). Since it's connected to the same voltage source, the power P = V²/R will double. As the heat generated is proportional to power, the heat generated will also be doubled.
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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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