When $n-p-n$ transistor is used as an amplifier :

When $n-p-n$ transistor is used as an amplifier :
  1. electrons move from base to collector
  2. holes move from emitter to base
  3. holes move from collector to base
  4. holes move from base to emitter

Solution

When $n-p$ - $n$ transistor is used as an amplifier, then collector is kept positive, so electrons move from base to collector.

Asked in: AP EAMCET 2003

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