Why does the emitter voltage rise in a CE amplifier with negative feedback?

[LvW]

So hydraulic analogy is useful to get your brain accustomed to working circuits "in your head" .
old jim

Yes - I fully agree.
As an interesting exercise, one could try to explain the amplifying properties of a transistor using the hydraulic analogy - in particular, if it seems to be possible that a tiny flow of water is able to control (with gain !) the water flow of a much larger river.

 

[Paul Colby]

if it seems to be possible that a tiny flow of water is able to control (with gain !) the water flow of a much larger river.

Pressure actuated valve on a much larger flow pipe? (Ah, this would be a FET)

 

[malemdk]

Voltage is work done per unit charge , therefore when we say voltage drop work is done between the resistor ie really a energy loss ,and it is physical quantity

 

[CraigHB]

You have to be careful using purely conceptual thinking with physics. Sometimes things behave in a way that's not intuitive. On the the other hand, the math does not always clarify dependencies such as the fact voltage has to be present before current will flow. Usually you need to understand the math first to understand the behavior conceptually. We use the term Voltage drop in a practical catch all manner, but the term fails to provide a sense of what's really going on there. The outward appearance is a voltage differential between one node and another, but there's physical behaviors taken for granted that result in those observable measurements.

 

[jim hardy]

We use the term Voltage drop in a practical catch all manner, but the term fails to provide a sense of what's really going on there.

"Voltage drop" is almost slang for voltage across something that is removing energy from a circuit, ie a load such as a motor or lamp
curiously
it's rare to hear the converse term "Voltage rise" describing voltage across something that deposits energy ie a source such as a battery or power supply.

 

[Grim Arrow]

Thanks everyone, your help is very helpful!