Help I Have An Electronics Test

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SUMMARY

The discussion centers on the operation of amplifiers, specifically regarding the behavior of output voltage in relation to an NPN transistor and its biasing. With a Vcc of 6V and a bias point around 3V, the output voltage can indeed drop below 0V due to the action of a capacitor discharging. When the output voltage falls below 3V, the capacitor discharges, effectively acting as a voltage source, which allows the output voltage to go negative relative to ground. This phenomenon clarifies why the output voltage does not clip at 0V.

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sanado
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After studying amplifiers and their operation, i suddenly realized today that i don't really know how they work at all.

Assume Vcc = 6V for an NPN transistor, biased correctly to fluctuate about 3V

In the Vout, once the DC part has been removed, how can the voltage possibly go lower than 0. If the amplifier is earthed, then isn't the minimal possible voltage 0? Wouldn't the V out at this point then be clipped and become 0? From the questions I've seen it obviously isn't but i don't understand why...Please help
 
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If the output voltage of the transistor is greater than 3V the capacitor will charge. If the output voltage goes below 3V the capacitor will discharge and act like a voltage source itself, with its positive side on the left and the negative side on the right.
 
Okay, that makes sense. So the capacitor acts as a voltage source and this is the reason why the voltage can drop below 0 (the Earth V)?
 

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