In the case of an AC circuit, the power loss in a resistive circuit.
Correct answer: A. Must be positive
- A. Must be positive
- B. Never can be positive
- C. May or may not be positive
- D. None
Explanation
Power loss in a resistor is due to the conversion of electrical energy into heat (P = I²R). Since both I² and R are always positive values, the power dissipated is always positive, regardless of whether the current is AC or DC.
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About Alternating Current
Alternating current varies periodically, so phase relationships become essential when current passes through a resistor, capacitor or inductor. The chapter distinguishes resistance from capacitive and inductive reactance, explains phase lead and lag, and connects changing electric and magnetic fields with the production and properties of electromagnetic waves.
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