Probably a Kirchhoff's laws problem

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The discussion revolves around solving a problem involving two infinitely long solenoids and their effect on a circuit with resistors R1, R2, and R3. The user is attempting to apply Kirchhoff's laws and the formula for electromotive force (EMF) to find the current in resistor R1, given the parameters of the solenoids and the rate of change of magnetic field. They have set up voltage equations based on the induced EMF but are struggling to derive the correct expression for I1. The user seeks assistance in identifying errors in their equation setup and understanding the induced currents in the circuit. The conversation highlights the challenges of applying theoretical concepts to practical circuit problems.
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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:

\epsilon = \frac{d\oint Bda}{dt}

Where it can be broken down into:

\epsilon = \frac{BA}{t}

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*r1^{2} + R2I2 + R1I1 = 0

G*pi*r2^{2} - 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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