For a given transistor amplifier circuit in CE configuration V_(CC)=1 V, R_C=1 k Ω, R_b=100 k Ω and β=100. Value of base current I_b is

Solution

Physics sir · 3 steps

V_(BB) is not given, so start from the collector side: find I_C first, then divide by β.

1. Pick the right loop. The base loop needs V_(BB), which is not given. The collector loop has everything we need: V_(CC) = 1 V and R_C = 1 kΩ.
2. Collector current. Take V_(CE) ≈ 0, so the whole of V_(CC) drops across R_C. Then I_C = V_(CC)/R_C = (1 V)/(1000 Ω) = 1 mA.

   I_b = I_C/β = (1 × 10⁻³ A)/100 = 1 × 10⁻⁵ A

3. So. I_b = 10 μA, which is option (d).

The idea to keep. In a CE circuit, if the base supply is unknown, get I_C from the collector loop using V_(CC) and R_C. Then I_B = I_C/β.

Answer from the NTA final answer key. Solution by PrepWiser.