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 _________.
Answer (integer)
750
Solution
<p>${R_B} = {{10 \times {{10}^{ - 3}}} \over {10 \times {{10}^{ - 6}}}}$</p>
<p>$= {10^3}\,\Omega$</p>
<p>$\therefore$ $${A_v} = \left( {{{\Delta {I_C}} \over {\Delta {I_B}}}} \right) \times \left( {{{{R_C}} \over {{R_B}}}} \right)$$</p>
<p>$$ = {{1.5 \times {{10}^{ - 3}}} \over {10 \times {{10}^{ - 6}}}} \times {{5 \times {{10}^3}} \over {1 \times {{10}^3}}}$$</p>
<p>$= {{1.5 \times 5} \over {10}} \times (1000)$</p>
<p>$= 750$</p>
About this question
Subject: Physics · Chapter: Electronic Devices · Topic: Transistors
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