Differences
This shows you the differences between two versions of the page.
| Both sides previous revision Previous revision Next revision | Previous revision | ||
| 184_notes:examples:week8_resistors_parallel [2021/06/28 23:47] – schram45 | 184_notes:examples:week8_resistors_parallel [2021/06/28 23:51] (current) – [Solution] schram45 | ||
|---|---|---|---|
| Line 18: | Line 18: | ||
| ===Approximations & Assumptions=== | ===Approximations & Assumptions=== | ||
| - | * The wire has very very small resistance when compared to the other resistors in the circuit: This means the wires will have no potential difference across them in our model. | ||
| - | * The circuit is in a steady state: It takes a finite amount of time for the circuit to set up a charge gradient and get to a steady state. Steady state means the current in any branch of the circuit is not changing with time. | ||
| - | * Approximating the battery as a mechanical battery. | ||
| - | * The resistors in the circuit are made of Ohmic materials. | ||
| * The wire has very very small resistance when compared to the other resistors in the circuit: This allows there to be no energy loss across the wires and no potential difference across them either simplifying down the model. | * The wire has very very small resistance when compared to the other resistors in the circuit: This allows there to be no energy loss across the wires and no potential difference across them either simplifying down the model. | ||
| * The circuit is in a steady state: It takes a finite amount of time for a circuit to reach steady state and set up a charge gradient. Making this assumption means the current is not changing with time in any branch of the circuit. | * The circuit is in a steady state: It takes a finite amount of time for a circuit to reach steady state and set up a charge gradient. Making this assumption means the current is not changing with time in any branch of the circuit. | ||
| Line 81: | Line 77: | ||
| We know enough potential differences to find the voltage across Resistor 2: | We know enough potential differences to find the voltage across Resistor 2: | ||
| ΔV2=ΔV3+ΔV4=8 V | ΔV2=ΔV3+ΔV4=8 V | ||
| + | One way in which we can evaluate the solution here is to pick a few other loops in the circuit and make sure they are still valid. There are often times many more loops in a circuit than the solution goes through. | ||
| + | |||
| That's all! Note that there are a lot of ways to do this problem, but we chose an approach that showcases the power of knowing equivalent resistance for resistors in parallel, and the power of the Loop Rule. See if you can create a different method for finding the unknowns. | That's all! Note that there are a lot of ways to do this problem, but we chose an approach that showcases the power of knowing equivalent resistance for resistors in parallel, and the power of the Loop Rule. See if you can create a different method for finding the unknowns. | ||