1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Single Transistor Overall Current Gain

  1. May 28, 2013 #1
    1. The problem statement, all variables and given/known data
    THe problem statement and given solutions are in this thread:


    I do not understand the equation for current gain:

    2. Relevant equations
    Ai = [itex]\alpha[/itex][itex]\frac{R4}{R4 + Ri}[/itex]

    3. The attempt at a solution
    I have pages of work on this, but basically what I know is [itex]\frac{Io}{Ie}[/itex] = [itex]\alpha[/itex]

    then [itex]\frac{Ie}{Ii}[/itex] must equal [itex]\frac{R4}{R4 + Ri}[/itex], I don't see that.
  2. jcsd
  3. May 28, 2013 #2


    User Avatar

    Staff: Mentor

    Why have you started a second thread for your own question?
  4. May 28, 2013 #3
    I started a second thread because I thought I had figured it out. I stated so in that thread, and thus expected no one would reply. I asked another question about this same circuit in a third thread.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted