In a common emitter configuration, a transistor has $\beta = 50$ and input resistance $1\, k\Omega$. If the peak value of a.c. input is $0.01\, V$ then the peak value of collector current is
- $0.01\, \mu A$
- $0.25\, \mu A$
- $100\, \mu A$
- $500\, \mu A$
The Correct Option is D
Solution and Explanation
Input resistance $=1 k \Omega$, input voltage $=0.01\, V$
Hence, $50=\frac{\Delta i_{C}}{\Delta i_{B}} $
$\Rightarrow \Delta i_{C}=50 \Delta i_{B}$
Also the change in base current is
$\Delta i_{B}=\frac{\text { input voltage }}{\text { input resistance }}=\frac{0.01}{1 \times 10^{3}}=10^{-5}\, A$
so, $\Delta i_{C}=50 \times 10^{-5}=500 \,\mu A$
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Concepts Used:
Semiconductors
Semiconductors are a crystalline solid materials, whose electrical conductivity lies between a conductor and an insulator. Semiconductors are mainly used in the manufacturing of electronic devices like capacitors, transistors, diodes, Integrated circuits, etc.
Properties of Semiconductor:
- Semiconductor acts like an insulator at Zero Kelvin. On increasing the temperature, it works as a conductor.
- Due to their exceptional electrical properties, semiconductors can be modified by doping to make semiconductor devices suitable for energy conversion, switches, and amplifiers.
- Lesser power losses.
Uses of Semiconductor:
- Semiconductors are widely used in manufacturing electronics devices like transistors, diodes, sensors, integrated circuits.
- Semiconductors are widely used in all electronic devices, like mobile phones, digital cameras, communication devices, trains, ATMs, etc.