Series Circuit Disconnected at Ammeter: Charge Flow?

AI Thread Summary
When a series circuit is disconnected at the negative terminal of an ammeter, the current stops immediately. Electrons take a finite time to "know" there is no longer a potential difference, but this propagation occurs at the speed of light, making the delay negligible. Once the electrons are no longer under an accelerating potential, they quickly lose their kinetic energy through collisions with ions. Even in low-resistivity conductors, any charge buildup is quickly neutralized, resulting in the conductor becoming equipotential. Thus, the flow of charge ceases almost instantaneously upon disconnection.
mich_v87
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Hey i have a little question to ask... when a series circuit is broken (disconnected) at the negative terminal of the ammeter , does the charge flow around the circuit until it gets to the end of the line at the ammeter and then stop ? or does it stop at the moment when it's broken?
 
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The short answer is "yes, the current stops immediately!"

However, if you want to get into "overanalysis" mode then there is a little more to the story.

a) It takes a finite time for electrons in the circuit to "know" that there is no longer a potential difference. That information propagates at the speed of light and, typically, the time for the information to arrive is VERY small.

b) Once electrons are no longer subject to an accelerating potential, they are stopped, again almost immediately, because they collide with ions and give up their kinetic energy.

c) Even in the case of very low resistivity, any charge buildup will promptly be halted so that the conductor will become an equipotential.
 
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