WBJEE · Physics · Semiconductors
A common emitter transistor amplifier is connected with a load resistance of \(6 \mathrm{k} \Omega\). When a small a.c. signal of 15 \(\mathrm{mV}\) is added to the base emitter voltage, the alternating base current is \(20 \mu \mathrm{A}\) and the alternating collector current is \(1.8 \mathrm{~mA}\). What is the voltage gain of the amplifier?
- A 90
- B 640
- C 900
- D 720
Answer & Solution
Correct Answer
(D) 720
Step-by-step Solution
Detailed explanation
Hint: \(R_{C}=6 \times 10^{3} \Omega\) \(\Delta \mathrm{l}_{\mathrm{B}} \mathrm{R}_{\mathrm{B}}=15 \times 10^{-3} \mathrm{~V}\) \(\Delta \mathrm{I}_{\mathrm{B}}=20 \times 10^{-6} \mathrm{~A}\) \(\Delta \mathrm{l}_{\mathrm{C}}=1.8 \times 10^{-3} \mathrm{~A}\)…
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