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--- 184_notes:combinations [2020/08/23 20:24] – dmcpadden
+++ 184_notes:combinations [2021/11/23 21:09] (current) – waterso8
@@ Line 21: / Line 21: @@
  $R_{3,4}=R_3+R_4$
  $R_{3,4}=24\Omega$
-At this point $R_5 $and$ R_{3,4} $are in parallel because they have the same potential difference across them. Note that$ R_5 $is //not// in parallel with$ R_3 $or with$ R_4 $but only with combination. We can then find the combined resistance of$ R_{2-4}$ then:
+At this point $R_2 $and$ R_{3,4} $are in parallel because they have the same potential difference across them. Note that$ R_2 $is //not// in parallel with$ R_3 $or with$ R_4 $but only with combination. We can then find the combined resistance of$ R_{2-4}$ then:
  $\frac{1}{R_{2-4}}=\frac{1}{R_2}+\frac{1}{R_{3,4}}$
  $R_{2-4}=(\frac{1}{7}+\frac{1}{24})^{-1}$
@@ Line 42: / Line 42: @@
   * **Color Coding** - Again, since we generally make the //__assumption that potential difference across wires is negligible__//, this means that everywhere along a single wire has the same electric potential. It can help to color code the pieces of the circuit that have the same electric potential (shown for the circuit above). Any circuit elements that have the same color transition (i.e., dark blue to orange) would be in parallel. In the example circuit, this shows why  $R_2$  is in parallel with the //combination// of  $R_3$  and  $R_4$ , but is not in parallel with only  $R_3$ .
   * **Look for easy combinations of circuit elements** - usually this means zooming in on the most complicated-looking part of the circuit and looking for elements that are definitely in series or definitely in parallel. If you replace those with an equivalent resistor, then continue looking for combinations, you can simplify the circuit down to something that is manageable. You can make as many combinations as you would like - just make sure you keep track of what you combined.
-  * **//When in doubt, use the loop and node rules//** - Because the loop rule is the statement of conservation of energy and the node rule is the statement of conservation of charge, these rules will **ALWAYS** work. It is possible to get circuit elements that are neither in series or parallel and cannot be combined into an equivalent resistance. You could also end up with a circuit with two power sources or batteries. Even in these cases, the loop and node rules will still work. (You may end up with a large system of equations to solve, but Wolfram Alpha and/or your calculator are pretty good at solving those.)
+  * **When in doubt, use the loop and node rules** - Because the loop rule is the statement of conservation of energy and the node rule is the statement of conservation of charge, these rules will **ALWAYS** work. It is possible to get circuit elements that are neither in series or parallel and cannot be combined into an equivalent resistance. You could also end up with a circuit with two power sources or batteries. Even in these cases, the loop and node rules will still work. (You may end up with a large system of equations to solve, but Wolfram Alpha and/or your calculator are pretty good at solving those.)
 ==== Other kinds of Circuits ====
@@ Line 48: / Line 48: @@
 ==== Examples ====
-[[:184_notes:examples:Week8_wheatstone|The Wheatstone Bridge]]
+  * [[:184_notes:examples:Week8_wheatstone|The Wheatstone Bridge]]
+    * Video Example: The Wheatstone Bridge
-[[:184_notes:examples:Week8_charge_discharge_caps_resistors|Challenge: Charging Capacitors through Resistors]]
+  * [[:184_notes:examples:Week8_charge_discharge_caps_resistors|Challenge: Charging Capacitors through Resistors]]
+    * Video Example: Charging Capacitors through Resistors
+{{youtube>uj2c1Tm7ttA?large}}
+{{youtube>D7-1N0Jbhv8?large}}