In a CE transistor amplifier there is a current and voltage gain associated with the circuit. In other words there is a power gain. Considering power a measure of energy, does the circuit violate conservation of energy?

In a CE transistor amplifier, there is a gain of current and voltage, which leads to a power gain. This seems like a violation of conservation of energy until one accounts for the supply voltage into the system, which is different form the input. Therefore, the extra power gained is from the supply power and hence the conservation of energy is not violated.


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