Question
Draw a circuit diagram of a common emitter amplifier using n-p-n transistor. Derive an expression for the current gain $\beta_{ac}.$
✓
Answer
- $\text{A}_{v} = \beta_{ac}.\frac{\text{R}_{L}}{\text{r}}$
$\therefore\beta_{ac} = \text{A}_{c}\frac{\text{r}}{\text{R}_{L}}$
Alternate Answer
$\beta_{ac} = \frac{\delta\text{l}_{c}}{\Delta\text{I}_{B}}$
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