In physics class my teacher is indicating that the electric potential in a wire remains constant until a resistor occurs. If the electrons in the wire are moving away from the negative terminal of the battery and $V = kQ/r,$ how can this be true? The electric potential in the battery would seem to drop in magnitude as the electrons got farther from the terminal. Please help!
Asked
Active
Viewed 149 times
0
-
5Does this answer your question? How electric currents can flow between 2 points at the same potential? – The Photon Mar 03 '22 at 04:57
-
1Read Section V. of Chabay and Sherwood's "Restructuring the introductory electricity and magnetism course" https://matterandinteractions.org/wp-content/uploads/2016/07/AJP-EandM.pdf and "A unified treatment of electrostatics and circuits" https://matterandinteractions.org/wp-content/uploads/2016/07/circuit.pdf . (They are on my to-read list.) Associated visualizations here: https://www.glowscript.org/#/user/matterandinteractions/folder/matterandinteractions/program/18-SurfaceCharge – robphy Mar 03 '22 at 05:20
-
When ever work is done on electrons, there is a drop in potential. The potential in a wire is NOT constant. You may also think of the wire having resistance which is why there is a decrease in potential. Your professor is strictly wrong. You can also easily see this by connecting a wire to a battery (for a short time as dangerous) and measure the potential difference using a volt meter to see that there is a drop in potential across various points in the wire. – jensen paull Mar 04 '22 at 15:50
-
Your professor is saying this because when a load of High resistance is in a circuit, the drop in potential across the wire is small in comparison. But definitely not zero. – jensen paull Mar 04 '22 at 15:54
1 Answers
0
It's correct to say that V=kQ/r but just speaking about an electric field generated in the space by a point charge valued as Q. In circuits you have just to think about "energy and work" of the points regardless of their distance from the battery poles: in the ideal wires you have no "friction" (resistance) in the flow of the charge column inside the wire, so all the energy is naturally spent to "press" that column through the resistors. In actual wires you have a small friction, the longer the wire the stronger the total friction (resistance of a wire), the ticker the wire the weaker the total friction.
