The current through a fixed resistor is doubled. By what factor does the power dissipated in it change?
Answer and explanation
Correct answer: A. It is multiplied by
- Step 1: with fixed.
- Step 2: Doubling multiplies by .
Answer
It is multiplied by .
Why not the others: It is multiplied by : treats power as proportional to current. It is multiplied by : cubes the current ratio. It stays the same: power depends on the current squared.
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