MHT CET · Physics · Semiconductors
In a common emitter transistor amplifier circuit, the current gain \(\alpha=0.8\). If the base current changes by \(3 \mu \mathrm{A}\) then the collector current changes by
- A \(4 \mu \mathrm{A}\)
- B \(6 \mu \mathrm{A}\)
- C \(12 \mu \mathrm{A}\)
- D \(24 \mu \mathrm{A}\)
Answer & Solution
Correct Answer
(C) \(12 \mu \mathrm{A}\)
Step-by-step Solution
Detailed explanation
\( \beta = \frac{\alpha}{1 - \alpha} = \frac{0.8}{1 - 0.8} = 4 \) \( \Delta I_C = \beta \cdot \Delta I_B = 4 \cdot 3 \, \mu \mathrm{A} = 12 \, \mu \mathrm{A} \)
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