A CE amplifier has voltage gain of 50, an input impedance of 2000 ohm and an output impedance of 400 ohm. The power gain of the amplifier will be

Options

A. 22500
B. 12500
C. 32500
D. 4100

Answer

To find the power gain of a Common Emitter (CE) amplifier, we can use the following steps:

### Step 1: Identify the given values
- Voltage Gain (Av) = 50
- Input Impedance (Zin) = 2000 ohms
- Output Impedance (Zout) = 400 ohms

### Step 2: Calculate the Resistance Gain (Rg)
The resistance gain is calculated using the formula:
\[ Rg = \frac{Zout}{Zin} \]
Substituting the values:
\[ Rg = \frac{400 \, \text{ohms}}{2000 \, \text{ohms}} = \frac{1}{5} \]

### Step 3: Calculate the Power Gain (Pg)
The power gain can be calculated using the formula:
\[ Pg = Av^2 \times Rg \]
Substituting the values:
\[ Pg = 50^2 \times \frac{1}{5} \]
Calculating \(50^2\):
\[ 50^2 = 2500 \]
Now substituting this back into the power gain formula:
\[ Pg = 2500 \times \frac{1}{5} = 2500 \div 5 = 500 \]

### Step 4: Final Calculation
Thus, the power gain of the amplifier is:
\[ Pg = 500 \]

### Conclusion
The power gain of the CE amplifier is 500.

---