Find the maximum induced emf in the large coil solenoid

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SUMMARY

The discussion focuses on calculating the maximum induced electromotive force (emf) in a large coil surrounding a solenoid. Given parameters include a solenoid with 7700 turns and a current described by I = I_0 sin(2πft), where I_0 = 30 A and f = 60 Hz. The magnetic field and flux equations are utilized, leading to the conclusion that the maximum induced emf can be derived from Faraday's Law of Induction and Ohm's Law. The user successfully calculated the magnetic fields and fluxes but required further guidance on applying these equations to find the induced emf.

PREREQUISITES
  • Understanding of Faraday's Law of Induction
  • Knowledge of Ohm's Law
  • Familiarity with magnetic field calculations in solenoids
  • Basic calculus for differentiation of magnetic flux
NEXT STEPS
  • Study the application of Faraday's Law in electromagnetic induction scenarios
  • Learn how to differentiate magnetic flux to find induced emf
  • Explore the relationship between resistance and induced voltage in circuits
  • Investigate the effects of frequency on induced emf in coils
USEFUL FOR

Students in physics or electrical engineering, particularly those studying electromagnetism and circuit theory, will benefit from this discussion.

kiwikahuna
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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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