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--- 184_notes:examples:week2_charged_thing_neutral_thing [2018/01/18 16:44] – [Solution] tallpaul
+++ 184_notes:examples:week2_charged_thing_neutral_thing [2018/05/17 15:56] (current) – curdemma
@@ Line 1: / Line 1: @@
-===== Interactions Between Charged and Neutral Objects =====
+[[184_notes:charge_and_matter|Return to Charge and Matter]]
+===== Example: Interactions Between Charged and Neutral Objects =====
 Suppose we have a positively charged object near a conductor. What happens to the charge distribution of the conductor when we bring an identical positively charged object near to the other side of the conductor? The situation is pictured below.
@@ Line 5: / Line 6: @@
 ===Facts===
-  * Electrons in a conductor can move easily through the material.
+  * Mobile charges in a conductor can move easily through the material.
   * The conductor is neutral (total net charge is $0 \text{ C}$).
-  * Opposites attract, so negatively charged electrons tend to be attracted to positively charged objects.
   * A smaller distance between charges means a stronger interaction.
@@ Line 25: / Line 25: @@
 ====Solution====
-A key fact here is that a **smaller distance between charges means a stronger interaction**. Consider the left-most region of the neutral conductor. This could be confusing since the positive left object attracts negatively charged particles to this region, while the right positive object repels positively charged particles to this region. Would this edge be neutral? Since the left positive is closer to this left-most region, its interaction is stronger than the right positive, and we end up with a net negative charge in this region. Similarly, the right-most region also has a net negative charge. Since we assumed the conductor is neutral, the positive charge needs to go somewhere, too! The only region remaining is the middle, which must have a net positive charge in order for the conductor to remain neutral. A diagram is shown below. \\
+A key fact here is that a **smaller distance between charges means a stronger interaction**. Consider the left-most region of the neutral conductor. The left object attracts negatively charged particles to this region, while the right object repels positively charged particles to this region. It turns out, though, this edge would **not** be neutral Since the left object is closer to this left-most region, its interaction is stronger than the right object, and we end up with a net negative charge in this region. Similarly, the right-most region also has a net negative charge. Since we assumed the conductor is neutral, the positive charge needs to go somewhere, too! The only region remaining is the middle, which must have a net positive charge in order for the conductor to remain neutral. A new representation is shown below. \\
 {{ 184_notes:2_charged_neutral_thing_solution.png?200 |Charge Distribution Induced From Two Sides, Solution}}