JEE Mains · Physics · STD 12 - 14. Semicondutor electronics
A transistor is used in common-emitter mode in an amplifier circuit. When a signal of \(10\, mV\) is added to the base-emitter voltage, the base current changes by \(10 \mu A\) and the collector current changes by \(1.5 \,mA\). The load resistance is \(5 \,k \Omega\). The voltage gain of the transistor will be
- A \(950\)
- B \(750\)
- C \(780\)
- D \(790\)
Answer & Solution
Correct Answer
(B) \(750\)
Step-by-step Solution
Detailed explanation
\(I _{ i }=\frac{10 mV }{10 \mu A }=10^{3} \Omega\) \(\beta=\frac{1.5 mA }{10 \mu A }=150\) \(A _{ V }=\left(\frac{ R _{0}}{ r _{ i }}\right) \beta=\left(\frac{5000}{1000}\right) \times 150=750\)
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