Find the maximum induced emf in the large coil solenoid

AI Thread Summary
The discussion focuses on calculating the maximum induced electromotive force (emf) in a large coil surrounding a solenoid. The solenoid's current varies sinusoidally, and the magnetic field and flux through the coils are derived using relevant equations. The user successfully calculates the magnetic fields and fluxes but struggles to connect these results to find the induced emf using Faraday's Law and Ohm's Law. Clarification is sought on how to apply these laws to solve for the maximum induced emf. The conversation emphasizes the importance of understanding the relationship between magnetic flux changes and induced emf.
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Homework Statement


Given: u_0 = 1.25664e-6
A 2 m long large coil with a radius of 14.6 cm and 320 turns surrounds a 4.2 m long solenoid with a radius of 4.6 cm and 7700 turns. The current in the solenoid changes as I = I_0 sin (2pi*f*t) where I_0= 30 A and f=60 Hz.Inside solenoid has 7700turns and outside coil has 320 turns. The equation for the emf is E = E_0sin(omega*t). There is also a resistor on the smaller coil that is 25 ohms. Find the maximum induced emf in the large coil. Answer in units of V.


Homework Equations


Magnetic field = B = u_0 * I / (2*pi*r)
Flux = BA


The Attempt at a Solution


I found the magnetic field of the solenoid (0.069115sin(120*pi*t)) and the area (0.006648). I then multipled BA to find the flux which is (0.000459 sin(120*pi*t))

Then I found the magnetic field of the outer coil ((0.006032sin(120*pi*t)) and the area to be 0.066966.
The magnetic flux is BA = (0.000404sin(120*pi*t))

Now I am truly stuck because I've no clue where to go from here. Please help! Many thanks.
 
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I think Ohm's Law and Faraday's Law would help:

\displaystyle V = iR

\displaystyle \oint\vec{E}\cdot d\vec{l} = \mathcal{E}_{ind} = -\frac{d\Phi_B}{dt}
 
Hmm...I'm still lost. Could you perhaps clarify what you mean and how those two equations would relate to each other.
 
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