JEE MainPhysicsAlternating CurrentMCQ+4 / −1
In an circuit the voltage applied is The resulting current in the circuit is The power consumption in the circuit is given by
- A
- B
- C
- D
View written solutionFree
Correct answer: C
-
Given expressions
The applied voltage is
The current is
-
Identify the phase difference
Comparing voltage and current:
- Voltage phase
- Current phase
So the current lags the voltage by
-
Use average power formula in AC circuit
The average power consumed in an AC circuit is
where
Therefore,
Since
we get
-
Alternative verification using instantaneous power
Instantaneous power is
Using
Over one complete cycle, the average of is zero, so average power is again
-
Check options
- A: ❌
- B: ❌
- C: ✅
- D: ❌
Hence, the correct option is C.
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