If collector current is 120 mA and base current is 2 mA and resistance gain is 3, what is power gain ?

Options

A. a.180
B. b.10800
C. c.`1.8`
D. d.18

Explanation

To find the power gain given the collector current (I_C), base current (I_B), and resistance gain, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Given Values:**
- Collector Current (I_C) = 120 mA = 120 × 10^-3 A
- Base Current (I_B) = 2 mA = 2 × 10^-3 A
- Resistance Gain (R_g) = 3

2. **Calculate Beta (β):**
- Beta (β) is defined as the ratio of collector current to base current.
\[ \beta = \frac{I_C}{I_B} \]
- Substituting the values:
\[ \beta = \frac{120 \times 10^{-3}}{2 \times 10^{-3}} = \frac{120}{2} = 60 \]

3. **Calculate Power Gain (P_g):**
- Power gain is given by the formula:
\[ P_g = R_g \times \beta^2 \]
- Substituting the values:
\[ P_g = 3 \times (60)^2 \]
- Calculating \(60^2\):
\[ 60^2 = 3600 \]
- Now substituting back into the power gain formula:
\[ P_g = 3 \times 3600 = 10800 \]

4. **Final Result:**
- The power gain is:
\[ P_g = 10800 \]