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what actually amplifies the current in CE mode of a transistor(npn here)? When the input is applied betn emitter and base, the forward biasing causes the electrons to move from source to the emitter say 100 electons. The same 100 electrons move towards the base where very few no. of electrons combine with holes say 2. they move out of the base towards source. so remaining electrons are 98 which move to the collector and out to the output circuit. So where is the current amplification? i have considered the Veb as 0.7 and Vce to be 1.