A 2cm diameter cylindrical solenoid of 10 loops and 20cm long

AI Thread Summary
The discussion revolves around calculating the electromotive force (EMF), current, magnetic field at the center, and self-inductance of a cylindrical solenoid in a changing magnetic field. Key equations mentioned include the EMF formula, which is the negative rate of change of magnetic flux, and the magnetic field inside a solenoid using Ampere's law. Participants express confusion about which magnetic field to use and how to find magnetic flux. Clarification is provided on using the change in magnetic field over time for EMF calculations. The discussion concludes with acknowledgment that understanding the flux equation significantly aids in solving the problem.
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Homework Statement



A 2cm diameter cylindrical solenoid of 10 loops and 20cm long is in a perpendicular magnetic field of 0.7Tesla directed away from you. The field increases to 2.7Tesla in 100ms. The loop has 8Ω.
What is the EMF?
What is the current?
What is the magnetic field of the center of the current?
What is the self inductance of the solenoid?


Homework Equations



Don't know where to start? Do I use the Bfield that the solenoid is in or the ΔB? When I used B with the eq: I=2radius / μN , I got an extreme current.

The Attempt at a Solution



Am I using the right equations?
eq: B = μNI / 2 radidus

 
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how do you find flux?

well flux is

\Phi=∫B*dA

emf is the time rate of change of the magnetic field

EMF= -\frac{d\Phi}{dt}

which in your case would be -(B2-B1)/t

To find the B field inside a solenoid you are going to need to do an amperian loop

to find i think B=μoNI/L

that should be enough to find what you need
 


Liquidxlax said:
how do you find flux?

well flux is

\Phi=∫B*dA

emf is the time rate of change of the magnetic field

EMF= -\frac{d\Phi}{dt}

which in your case would be -(B2-B1)/t

To find the B field inside a solenoid you are going to need to do an amperian loop

to find i think B=μoNI/L

that should be enough to find what you need

Thank you ... \Phi=∫B*dA... This equation helped a lot.
 
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