Differences

This shows you the differences between two versions of the page.

--- 184_notes:q_in_wires [2021/02/18 20:14] – bartonmo
+++ 184_notes:q_in_wires [2021/02/18 21:17] – bartonmo
@@ Line 8: / Line 8: @@
 We have already talked about how to model a battery as a separation of charges. However, if we connect the two ends of the battery with a conducting wire, what happens to the charge distribution in the wire? Using [[184_notes:batteries|the mechanical model of battery]] and [[184_notes:charge_and_matter|what we know about conductors]], these notes will discuss how charges interact in the wire and how that impacts the electron current.
-{{youtube>Sxntc0SVkUQ?large}}
+{{youtube>Sxntc0SVkUQ?medium }}
@@ Line 52: / Line 52: @@
   - If the force that pushes the electrons comes from the surface of the wires, then the proximity to the battery doesn't matter - there will still be a constant electric field in the wire to move the electrons.
-Thus, surface charges as the model for how charges move through wires is far more consistent with the observations we have in real circuits in everyday life. If you have a very large battery (also called a high voltage power supply) it is actually possible to observe the surface charges on a wire. Here's a video demonstrating it.
+Thus, surface charges as the model for how charges move through wires is far more consistent with the observations we have in real circuits in everyday life. If you have a very large battery (also called a high voltage power supply) it is actually possible to observe the surface charges on a wire.
+ {{ youtube>U7RLg-691eQ?medium}}
+In this video, you can see the mechanical effects of surface charge when a piece of foil is held by the positive end, negative end, and neutral center of the wire. On the ends of the wire, the foil is initially attracted, polarized, and then repelled. Since the surface charge at the center of the wire is 0 nothing happens to the foil. A metal pen can also be used to see what kind of charge the foil has picked up based on if it is attracted to or repelled by the pen.
-{{ youtube>U7RLg-691eQ?medium }}
 ==== Examples ====
 [[:184_notes:examples:Week6_charges_circuit|Charge Distribution on the Bends of a Circuit]]