I think the hose and marble analogy is still a good one
garden hose - conductor
marbles - electrons, charge carriers
Current - number of marbles thru a cross sectional area of the hose per second
Voltage - the force your using to push the marbles thru the hose
Resistance - measure of how easy/hard hose allows flow of marbles
If you make hose diameter smaller (increase resistance) you need to increase voltage push to maintain same marble current thru hose if you make hose diameter larger (lower resistance) then you need lower voltage push to maintain same current hose diameter smaller & voltage same the less marbles out the end -> less current hose diamter larger & voltage same get more marbles thru -> higher current
the analogy also works for signal velocity vs electron drift
signal velocity would be how fast marbles start coming out the end after you start pushing on them and if the hose was already full of marbles then they start popping out the end almost instantaneously
electron drift velocity would be how long it takes for a specific marble to work its way thru the hose
a transistor is a three terminal device. the two main terminals are ends of the hose. The third terminal is like a valve in the middle of the hose. When you open the vavle the resistance between the two main terminals is very low and allows current to flo.
Close the valve and the resistance between the two main terminals is very high and does not allow current to flo.
So the basic transistor config is a on/off switch.
An amplifier is operating this valve in an approximately linear region between off and on. If you want to amplify a small audio signal you connect it to the valve.
When signal is high the valve is more open and allows more current flow and signal low valve is more closed less current.
If you tap the two main terminals as your output you get the ‘amplified’ version of the signal you applied to the valve (with amp power coming from one of the main terminals)
adding this to the stack of projects i’ll never finish (next to the stack of books i’ll never read)