Probably a Kirchhoff's laws problem

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SUMMARY

This discussion focuses on solving a circuit problem involving two infinitely long solenoids and their induced currents using Kirchhoff's laws. The parameters provided include solenoid lengths (L1 = 0.473 m, L2 = 0.473 m), radii (r1 = 0.112 m, r2 = 0.154 m), and resistances (R1 = 6.13 Ω, R2 = 5.10 Ω, R3 = 3.28 Ω). The induced magnetic field is increasing at a rate of 122 T/s, and the user is attempting to calculate the current in resistor R1 using the equation for electromotive force (ε = d∮Bda/dt). The user has set up voltage loops but is struggling to derive the correct equations for the currents.

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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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