Probably a Kirchhoff's laws problem

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In summary, the conversation discusses a problem involving two infinitely long solenoids threading a circuit and the resulting induced currents. The relevant equations are mentioned, and the attempt at a solution involves setting up voltage loops and solving for the current in resistor R1. However, the equations keep coming out wrong and the question is considered confusing. The conversation ends with a suggestion to fix a problem with the template being added every time the post is previewed.
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Ownaginatious
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Homework Statement



Two infinitely long solenoids (seen in cross-section) thread a circuit as shown in the figure below.

http://capa.physics.mcmaster.ca/figures/sb/Graph31/sb-pic3152.png

Assume that L1 = 0.473 m, L2 = 0.473 m, H = 0.473 m, r1 = 0.112 m, r2 = 0.154 m, R1 = 6.13 Ω, R2 = 5.10 Ω and R3 = 3.28 Ω. The magnitude of B inside each is the same and is increasing at the rate of 122 T/s. What is the current in resistor R1?

Homework Equations



I believe the relevant equations to this are:

[tex]\epsilon[/tex] = [tex]\frac{d\oint Bda}{dt}[/tex]

Where it can be broken down into:

[tex]\epsilon[/tex] = [tex]\frac{BA}{t}[/tex]

That's how I'm trying to get the voltage for the loops.

The Attempt at a Solution



I'm trying it with the following voltage loops where the current runs up R2 and branches into the current going to R1 and R3.

So far I've set up the following voltage loops, both taken going clockwise:

(I've made the B/t equal to just G since it is given)

G*pi*[tex]r1^{2}[/tex] + R2I2 + R1I1 = 0

G*pi*[tex]r2^{2}[/tex] - R3I3 - R2I2 = 0

I2 = I1 + I3

I keep rearranging everything for I1, but it keeps coming out wrong. Could anyone perhaps tell me what I've done wrong in setting up my equations? I find this question rather confusing since we really haven't done much with induced currents in circuits.

Any help would be greatly appreciated.

Thanks!

P.S. Whoever is in charge here should consider fixing that problem where a new template is added every time I preview my post... it's very annoying.
 
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I would respond by saying that the problem presented is indeed a Kirchhoff's laws problem, specifically dealing with the law of electromagnetic induction. The equations that you have identified are correct and can be used to solve the problem. However, it seems that you may have made a mistake in your setup of the voltage loops. It may be helpful to draw a diagram of the circuit and label the voltage loops and currents to ensure that they are correctly set up. Additionally, you may want to double check your calculations to make sure that all units are consistent and that you are using the correct values for the given variables. It is also important to note that the direction of the induced current may depend on the direction of the changing magnetic field, which in this case is increasing. Overall, it may be helpful to approach the problem step by step and check your work at each stage to ensure accuracy.
 

What are Kirchhoff's laws?

Kirchhoff's laws are a set of rules that describe the behavior of electric circuits. They are used to calculate the currents and voltages in a circuit based on the properties of the components and the arrangement of the circuit.

What are the two laws in Kirchhoff's laws?

The two laws in Kirchhoff's laws are Kirchhoff's current law (KCL) and Kirchhoff's voltage law (KVL). KCL states that the sum of the currents entering a node (or junction) in a circuit must equal the sum of the currents leaving the node. KVL states that the sum of the voltages around a closed loop in a circuit must equal zero.

What types of circuits can Kirchhoff's laws be applied to?

Kirchhoff's laws can be applied to any type of electric circuit, including series, parallel, and complex circuits. They can also be applied to both DC and AC circuits.

How do I use Kirchhoff's laws to solve a problem?

To solve a problem using Kirchhoff's laws, you first need to draw a circuit diagram and label all the components and their properties (such as resistances and voltages). Then, apply KCL and KVL to the appropriate nodes and loops in the circuit to create a system of equations. Finally, solve the equations to find the unknown currents and voltages in the circuit.

What are some common mistakes when applying Kirchhoff's laws?

Some common mistakes when applying Kirchhoff's laws include forgetting to include all the components and their properties in the circuit diagram, not properly labeling the direction of currents and voltages, and incorrectly applying KCL or KVL. It is important to carefully follow the rules and steps when solving a problem using Kirchhoff's laws to avoid these mistakes.

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