For a transistor the value of `alpha` is `0.9`. `beta` value is

Options

A. `9`
B. `0.9`
C. `0.09`
D. `90`

Explanation

To find the value of `beta` for a transistor given that `alpha` is `0.9`, we can use the relationship between `alpha` and `beta`. The relationship is given by the formula:

\[ \beta = \frac{\alpha}{1 - \alpha} \]

### Step-by-Step Solution:

1. **Identify the given value of alpha**:
- We know that \( \alpha = 0.9 \).

2. **Substitute alpha into the formula**:
- Plug the value of \( \alpha \) into the formula for \( \beta \):
\[ \beta = \frac{0.9}{1 - 0.9} \]

3. **Calculate the denominator**:
- Calculate \( 1 - 0.9 \):
\[ 1 - 0.9 = 0.1 \]

4. **Perform the division**:
- Now substitute back into the equation:
\[ \beta = \frac{0.9}{0.1} \]

5. **Calculate the final value of beta**:
- Perform the division:
\[ \beta = 9 \]

### Final Answer:
The value of \( \beta \) is \( 9 \).

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