Power Gain of CE amplifier circuit is given by

Options

A. Voltage gain × current gain
B. Voltage gain/Current gain
C. Current gain/Voltage gain
D. (Voltage gain)^2 × current gain

Answer

To solve the question regarding the power gain of a Common Emitter (CE) amplifier circuit, we can break it down into a series of steps:

### Step-by-Step Solution:

1. **Understanding Power Gain**:
Power gain (denoted as \( G_P \)) is defined as the ratio of output power (\( P_{out} \)) to input power (\( P_{in} \)).
\[ G_P = \frac{P_{out}}{P_{in}} \]

2. **Expressing Power in Terms of Voltage and Current**:
Power can be expressed in terms of voltage and current. The output power can be written as:
\[ P_{out} = V_{out} \times I_{out} \]
Similarly, the input power can be expressed as:
\[ P_{in} = V_{in} \times I_{in} \]

3. **Substituting Power Expressions into Power Gain**:
By substituting the expressions for \( P_{out} \) and \( P_{in} \) into the power gain formula, we get:
\[ G_P = \frac{V_{out} \times I_{out}}{V_{in} \times I_{in}} \]

4. **Separating Voltage and Current Terms**:
We can rearrange the equation to separate the voltage and current terms:
\[ G_P = \left(\frac{V_{out}}{V_{in}}\right) \times \left(\frac{I_{out}}{I_{in}}\right) \]

5. **Identifying Voltage Gain and Current Gain**:
Here, \( \frac{V_{out}}{V_{in}} \) is defined as the voltage gain (\( A_V \)), and \( \frac{I_{out}}{I_{in}} \) is defined as the current gain (\( A_I \)). Therefore, we can express the power gain as:
\[ G_P = A_V \times A_I \]

6. **Conclusion**:
Thus, the power gain of a CE amplifier circuit is the product of the voltage gain and the current gain.

### Final Answer:
The power gain of a CE amplifier circuit is given by:
\[ G_P = A_V \times A_I \]