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Question
In the circuit shown in figure, when the input voltage of the base resistance is 10 V, Vbe is zero and Vce is also zero. Find the values of Ib, Ic and β.
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Solution
According to the problem, Vi = 10 V, Resistance, RB = 400 kΩ, VBE = 0, VCE = 0 and RC = 3 kΩ
`V_i - V_(BE) = R_BI_B`
`I_B = ("Voltage across" R_B)/R_B`
= `10/(400 xx 10^3)`
= `25 xx 10^-6` A
= 25 μA
Voltage across RC = 10 V
`V_(CC) - V_(CE) = I_CR_C`
`I_C = ("Voltage across" R_C)/R_C`
= `10/(3 xx 10^3)`
= `3.33 xx 10^-3` A
= 3.33 mA
β = `I_C/I_B`
= `(3.33 xx 10^-3)/(25 xx 10^-6)`
= `1.33 xx 10^2`
= 133
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