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There exists only one current in a circuit: What I take that to mean is simply that there is a movement of electrons through the circuit wires.
Does that mean that electrons move at different speeds at distinct parts of a circuit like, say, before and after a resistor? No, that would imply a different dQ/dt, therefore different currents. I'm confused as to how we can measure different voltages before and after a resistor in a circuit, but the current be the same along the circuit..
Any simple circuit like the picture attached..
There is a voltage drop across the resistor, but if there's different voltages, why not different currents?
The question came up looking at this thread:
https://www.physicsforums.com/showthread.php?t=316323"
where each of the 6 LED's in series, for instance, each require 15 mA. If the same current occurs through all the LED's, then all you'd need to figure out is the equivalent resistance, yes?
Does that mean that electrons move at different speeds at distinct parts of a circuit like, say, before and after a resistor? No, that would imply a different dQ/dt, therefore different currents. I'm confused as to how we can measure different voltages before and after a resistor in a circuit, but the current be the same along the circuit..
Any simple circuit like the picture attached..
There is a voltage drop across the resistor, but if there's different voltages, why not different currents?
The question came up looking at this thread:
https://www.physicsforums.com/showthread.php?t=316323"
where each of the 6 LED's in series, for instance, each require 15 mA. If the same current occurs through all the LED's, then all you'd need to figure out is the equivalent resistance, yes?
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