Can anyone explain how a transistor can amplify voltage or current? According to me, amplification means – You send in something small, it comes out bigger. Say for example, I want to amplify a sound wave. I whisper to a sound amplifier, & it comes out say, 5 times bigger(depending on the amplification factor)
But when I read about Transistor Amplifying action, all text books say that since a small change in the Base current ΔIb but a corresponding large change in Emitter current ΔIe, there is amplification. But where is amplification? What is being amplified as I've defined it? Is my understanding of the term amplification wrong? And how is current being transferred from a low resistance area to a high resistance area?
I think I've understood how the transistor is constructed & how the currents flow. So can anyone explain the transistor amplification action clearly & relate it to what I understand about amplification.