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 $\times$ 104. The value of x is _____________.
Answer (integer)
2
Solution
<p>Power gain $$ = {\left[ {{{\Delta {i_C}} \over {\Delta {i_B}}}} \right]^2} \times {{{R_o}} \over {{R_i}}}$$</p>
<p>$$ = {\left[ {{{{{10}^{ - 2}}} \over {{{10}^{ - 4}}}}} \right]^2} \times {2 \over 1}$$</p>
<p>$= 2 \times {10^4}$</p>
<p>$\Rightarrow x = 2$</p>
About this question
Subject: Physics · Chapter: Electronic Devices · Topic: Transistors
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