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In the study of transistors as an amplif...

In the study of transistors as an amplifier, if `alpha=I_(c)//I_(c)` and `beta=I_(c)//I_(b)`, where `I_(c),I_(b)` and `I_(e)` are the collector, base and emitter currents, then

A

`beta=(1-alpha)/(alpha)`

B

`beta=(alpha)/(1-alpha)`

C

`beta=(alpha)/(1+alpha)`

D

`beta=(1+alpha)/(alpha)`

Text Solution

Verified by Experts

The correct Answer is:
B
Since, `alpha=(I_(c))/(I_(e)), beta=(I_(c))/(I_(b))`
and `I_(e)=I_(c)+I_(b)`
`implies(I_(e))/(I_(c))=1+(I_(b))/(I_(c))implies(1)/(alpha)=1+(1)/(beta)impliesbeta=(alpha)/(1-alpha)`
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