Does electricity have momentum?

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Electricity does not exhibit momentum in the same way as water in a pump system, despite charges having momentum. The flow of electric current is determined by potential differences rather than the physical layout of the circuit, meaning bending wires does not affect voltages or currents. In a uniform-diameter pipe, water flow remains consistent due to its incompressibility, contrasting with the behavior of electric charges. While moving charges do possess momentum, it is largely irrelevant in typical circuit operations. Understanding these differences clarifies why analogies between water flow and electricity can be misleading.
BenChicago
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w = x = y = z ,

If this were a pump system with water, I think the pressure and flow would be much higher at reading #2, because water has momentum? What about electricity, would the current be higher at #2?
 

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If you create a circuit, and then bend the wires around in arbitrary ways, you will not change anything about the voltages and currents.

Charges have momentum, and of course charges have to move for electricity to flow, but it isn't as simple as the case of water (part of the reason the analogy is bad). If current flows from one end of a wire to the other, there is no electron that traveled that whole distance. Energy is flowing in response to potential differences, and (assuming the wire has no resistance) it doesn't matter what the wire does between points A and B, just the potential at the two points. That's why you can draw schematic circuit diagrams without worrying about the actual layout of items in space.
 
BenChicago said:
w = x = y = z ,

If this were a pump system with water, I think the pressure and flow would be much higher at reading #2, because water has momentum? What about electricity, would the current be higher at #2?

How could the water flow be different at different parts of the uniform-diameter pipe? Water is basically incompressible, so the flow rate has to be uniform in that uniform pipe.
 
berkeman said:
How could the water flow be different at different parts of the uniform-diameter pipe? Water is basically incompressible, so the flow rate has to be uniform in that uniform pipe.

I think he's thinking if you bend the pipe, water will have laminar or turbulent flow and all that?
 
Yes, moving charges do have momentum. But it is inconsequential in most circuits.
 
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