For a constant collector-emitter voltage of $8 \mathrm{~V}$, the collector current of a transistor reached to the value of $6 \mathrm{~mA}$ from $4 \mathrm{~mA}$, whereas base current changed from $20 \,\mu \mathrm{A}$ to $25 \,\mu \mathrm{A}$ value. If transistor is in active state, small signal current gain (current amplification factor) will be :
Solution
<p>$\beta = {{\Delta {I_C}} \over {\Delta {I_B}}}$</p>
<p>$= {{(6 - 4) \times {{10}^{ - 3}}} \over {(25 - 20) \times {{10}^{ - 6}}}}$</p>
<p>$= {2 \over 5} \times {10^3}$</p>
<p>$= 400$</p>
About this question
Subject: Physics · Chapter: Electronic Devices · Topic: Transistors
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