In the `CB` mode of a transistor, when the collector voltage is changed by `0.5` volt. The collector current changes by `0.05 mA`. The output resistance will be

Options

A. `10 k Omega`
B. `20 k Omega`
C. `5 k Omega`
D. `2.5 k Omega`

Explanation

To find the output resistance in the common base (CB) mode of a transistor, we can use the formula for output resistance, which is defined as the change in collector voltage divided by the change in collector current.

### Step-by-Step Solution:

1. **Identify the given values**:
- Change in collector voltage (ΔV_C) = 0.5 volts
- Change in collector current (ΔI_C) = 0.05 mA

2. **Convert the change in collector current to amperes**:
- ΔI_C = 0.05 mA = 0.05 × 10^(-3) A = 0.00005 A

3. **Use the formula for output resistance**:
- The output resistance (R_output) is given by the formula:
\[ R_{output} = \frac{\Delta V_C}{\Delta I_C} \]

4. **Substitute the values into the formula**:
- Substituting the values we have:
\[ R_{output} = \frac{0.5 \text{ V}}{0.00005 \text{ A}} \]

5. **Calculate the output resistance**:
- Performing the division:
\[ R_{output} = \frac{0.5}{0.00005} = 10000 \text{ ohms} \]
- This can also be expressed as:
\[ R_{output} = 10^4 \text{ ohms} = 10 \text{ kilo ohms} \]

6. **Conclusion**:
- Therefore, the output resistance is 10 kilo ohms.

### Final Answer:
The output resistance is **10 kilo ohms**.

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