Assertion (A): In a purely resistive AC circuit, voltage and current are in phase. Reason (R): Resistors do not store energy; they dissipate it as heat. MCQ with Answer and Explanation

Assertion (A): In a purely resistive AC circuit, voltage and current are in phase. Reason (R): Resistors do not store energy; they dissipate it as heat.
A. Both A and R are true, but R is not the correct explanation of A
B. A is false, but R is true
C. Both A and R are true, and R is the correct explanation of A
D. A is true, but R is false
Answer: Option C
Solution (By JKSSB Mock Tests)
Assertion is true: in resistive AC circuits, V and I reach peaks simultaneously (phase difference 0°). Reason is true and explains A: resistors obey Ohm's law instantaneously (V=IR), with no energy storage mechanism (unlike capacitors/inductors that cause phase shifts via energy storage/release). Thus, no phase difference arises. Memory aid: 'Resistors: V and I in phase; Capacitors: I leads V; Inductors: V leads I'. This assertion-reason question tests AC circuit fundamentals, frequently examined. Always link phase behavior to energy storage properties of components.

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