A transistor is operated in common emitter configuration at constant collector voltage VC = 1.5 V such that a change in the base current from 100 µA to 150 µA produces a change in the collector current from 5 mA to 10 mA. The current gain (β) is :
- 50
- 70
- 100
- 125
The Correct Option is C
Solution and Explanation
Transistor Current Gain (\(\beta\)): \(\beta\) (current gain) is given by the change in collector current (\(\triangle \text{I}_C\)) divided by the change in base current (\(\triangle \text{I}_B\)).
In this case, \(\triangle \text{I}_C\) = 10 mA - 5 mA = 5 mA
and \(\triangle \text{I}_B\) = 150 μA - 100 μA = 50 μA.
So, \(\beta\) = \(\frac{\triangle \text{I}_C}{\triangle \text{I}_B}\) =\(\frac{5 mA}{50 \mu A}\) = 100.
Therefore, the correct option is (C): 100
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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.