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In a common emitter configuration with suitable bias, it is given that R_L is the load resistance and R_BE is small signal dynamic resistance (input side). Then, voltage gain, current gain and power gain are given, respectively, by: [β is current gain, I_B, I_C, I_E are given base, collector and emitter currents] [JEE-Main On line-2018]
- β R_L/R_BE, ΔI_E/ΔI_B, β² R_L/R_BE
- β² R_L/R_BE, ΔI_C/ΔI_B, β R_L/R_BE
- β² R_L/R_BE, ΔI_E/ΔI_B, β² R_L/R_BE
- β R_L/R_BE, ΔI_C/ΔI_B, β² R_L/R_BE
Correct answer: β R_L/R_BE, ΔI_C/ΔI_B, β² R_L/R_BE
Solution
The correct option accurately reflects the relationships in a common emitter configuration, where the voltage gain is determined by the ratio of load resistance to small signal resistance, the current gain is the ratio of collector current change to base current change, and the power gain is the square of the current gain multiplied by the voltage gain.
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