JEE Mains · Physics · STD 12 - 14. Semicondutor electronics
A transistor is used in an amplifier circuit in common emitter mode. If the base current changes by \(100 \,\mu A\), it brings a change of \(10 \,mA\) in collector current. If the load resistance is \(2 \,k \Omega\) and input resistance is \(1 \,k \Omega\), the value of power gain is \(x \times 10^{4}\). The value of \(x\) is_________
- A \(2\)
- B \(5\)
- C \(3\)
- D \(1\)
Answer & Solution
Correct Answer
(A) \(2\)
Step-by-step Solution
Detailed explanation
\(\Delta i _{ B }=100 \,\mu A \quad \beta=\frac{\Delta i _{ C }}{\Delta i _{ B }}\) \(\Delta i _{ c }=10 \,mA\) power \(=\beta^{2} \times \frac{R_{0}}{R_{i n}}\) Power \(=\left(\frac{10}{0.1}\right)^{2} \times \frac{2}{1}\) Power \(=100 \times 100 \times 2\) Gain…
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