Question

In n-p-n transistor circuit, the collector current is `10 mA`. If `90%` of the holes reach the collector, find emitter and base currents.
A. 10 mA, 1 mA
B. 22 mA,11 mA
C. 11 mA, 1 mA
D. 20 mA, 10 mA

Answer 1

Correct Answer - C
Here, `I_C`=10 mA, as 90% of the holes reach the collector, so the collector current,
`I_C`=90% of `I_E=90/100I_E`
or `I_E=100/90 I_C=100/90xx10=11` mA
Now, base current, `I_B=I_E-I_C`=11-10=1 mA