In a common- emitter circuit, coIIector- emitter voItage is fixed at 5V. For base currents 30`mu`A and 40 `mu`A, the coIIector currents are 8.2 mA and 9.4 mA respec- tiveIy. CaIcuIate current gain of the circuit.

Explanation

The change in base current
`Delta I_(B)=(40-30) muA=10muA`
The change in collector current
`DeltaI_(C)=(9.4-8.2)=1.2` mA =`1.2xx10^(3) mu"A"=1200 mu` A
`:. " "beta=(DeltaI_(C))/(DeltaI_(B))=(1200mu"A")/(10mu"A")=120`