Question

Given that VS = 3V, VBE = 0.3V, IC = 9mA, and R1 = 1kΩ, calculate the base current of the transistor Q1 using KVL. Also find the current gain (beta ) of the transistor Q1.

Answer 1

We know that load line equation

$V_{BB}=V_{BE}+I_BR_B\\V_{BB}=V_S\\V_{S}=V_{BE}+I_BR_B$

Put value

$3=0.3+I_B\times1000$

$2.7=I_B\times1000$

$I_B=2.7mA$

$I_c=9mA$

$\beta=\frac{I_c}{I_B}=\frac{9\times10^{-3}}{2.7\times10^{-3}}=$ 3.33