NTA Abhyas JEE Main2020PhysicsSemiconductorsPractice
In a common emitter transistor amplifier, signal voltage across the collector resistance of 2 k Ω is 2 volt . What should be the value of resistance R B in series with V B B voltage supply of 2 volt in the input circuit, if the D . C . base current is 10 times the signal current in R B ? ( given base emitter voltage V B E = 0.6 volt, current amplification factor β a c ≈ β d c = 100 )
Options
- A7   kΩ
- B26   kΩ
- C10   kΩ
- D14   kΩ
Correct answer
D. 14   kΩ
Step-by-step solution
i c AC = V out  AC R C = 2  volt  2   kΩ = 1   mA i B AC = i c AC β ac = 1   mA 100 = 0 . 01   mA i B DC = 10 i B AC = 0 . 1   mA = 10 - 4   A R B = V i B = 2 - 0 . 6 10 - 4 = 14   kΩ