Average power in the L-C-R circuit depends upon

Options

A. current
B. phase difference only
C. EMF
D. current, EMF and phase difference

Answer

To solve the question about what the average power in an L-C-R circuit depends upon, we can follow these steps:

### Step 1: Understand the formula for average power in an L-C-R circuit
The average power (P) in an L-C-R circuit can be expressed using the formula:
\[ P = V_{RMS} \times I_{RMS} \times \cos \phi \]
where:
- \( V_{RMS} \) is the root mean square voltage,
- \( I_{RMS} \) is the root mean square current,
- \( \cos \phi \) is the power factor, which is related to the phase difference (φ) between the voltage and current.

### Step 2: Identify the components of the formula
From the formula, we can see that:
- Average power (P) depends on the RMS voltage (\( V_{RMS} \)).
- Average power (P) depends on the RMS current (\( I_{RMS} \)).
- Average power (P) depends on the power factor (\( \cos \phi \)), which is influenced by the phase difference (φ) between the voltage and current.

### Step 3: Conclude the dependencies
Since average power depends on all three quantities—RMS voltage, RMS current, and the power factor (which is related to the phase difference)—we can conclude that:
- Average power in an L-C-R circuit depends on the current, EMF (voltage), and phase difference.

### Final Answer
The average power in an L-C-R circuit depends upon:
- Current (I)
- EMF (Voltage, V)
- Phase difference (φ)

Thus, the correct answer is option D: Average power is dependent on current, EMF, and phase difference.

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