AC Power Rating and Values – Rankers Physics

Power in AC Circuits: Practice Problem & Solution

Assertion (A): The power rating of an element in \(AC\) circuit refers to average power rating. Reason (R): A given value for \(AC\) voltage or current is usually its average value.  
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false

Short Solution (Best for NEET):

To solve this problem, we apply the core principles of Power in AC Circuits. Understanding the underlying formula is key to arriving at the correct answer below:

Power rating of \(AC\) devices always refers to average power. However, \(AC\) voltage or current values (e.g., 220V) are typically Root Mean Square (RMS) values, not average values. For a full cycle, the average value of sinusoidal \(AC\) is zero.

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Similar Practice Questions

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1. The value of capacitance \(C\) in an LCR series circuit with inductance \(L = 50\) mH, connected with a voltage source of angular frequency \(100\) rad/s so that current in the circuit becomes maximum, is:
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