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amaresh92
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1. Homework Statement [/b]
calculate alpha DC (emitter to collector dc current gain) and beta DC (base to collector dc current gain) for a transistor which has Ic=2.5ma, Ie=2.6ma .
formula 1) alpha DC=Ic/Ie.
formula 2) beta DC =Ic/Ib.
formula 3) beta DC = alpha DC/(1-alpha DC)
formula 4) Ib=Ie-Ic
using formula 1)
alpha dc=Ic/Ie
=2.5/2.6
=0.96
using formula 4)
Ib=Ie-Ic
=2.6-2.5
=0.1ma using formula 2)
beta DC =Ic/Ib
=2.5/0.1
=25
using formula 3)
beta DC = alpha DC/(1-alpha DC)
= 0.96/(1-0.96)
=24
my doubt is, from above calculation for beta DC using formula 2 and 3 we are getting two different values for beta DC. so which one is correct and under which condition or how i should use these two formula? In the sense when i should use formula 2 and formula 3.
advanced thanks
calculate alpha DC (emitter to collector dc current gain) and beta DC (base to collector dc current gain) for a transistor which has Ic=2.5ma, Ie=2.6ma .
Homework Equations
formula 1) alpha DC=Ic/Ie.
formula 2) beta DC =Ic/Ib.
formula 3) beta DC = alpha DC/(1-alpha DC)
formula 4) Ib=Ie-Ic
The Attempt at a Solution
using formula 1)
alpha dc=Ic/Ie
=2.5/2.6
=0.96
using formula 4)
Ib=Ie-Ic
=2.6-2.5
=0.1ma using formula 2)
beta DC =Ic/Ib
=2.5/0.1
=25
using formula 3)
beta DC = alpha DC/(1-alpha DC)
= 0.96/(1-0.96)
=24
my doubt is, from above calculation for beta DC using formula 2 and 3 we are getting two different values for beta DC. so which one is correct and under which condition or how i should use these two formula? In the sense when i should use formula 2 and formula 3.
advanced thanks