(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Two circular coils are concentric and lie in the same plane. The inner coil contains 110 turns of wire, has a radius of 0.010 m, and carries a current of 5.6 A. The outer coil contains 190 turns and has a radius of 0.014 m. What must be the magnitude of the current in the outer coil, such that the net magnetic field at the common center of the two coils is zero?

2. Relevant equations

B=(constant)IN/2R

3. The attempt at a solution

Ok so I have I1=5.6 A

R1=.010 m

N1=110

R2=.014 m

N2=190

I2=?

I think that I have to use that equation somehow and set them equal to each other, but I'm lost after that. Perhaps I'm using the wrong equation entirely? Any help is much appreciated!!

Edit: Do I just solve for B1 and then set that equal to the equation for the 2nd coil (only make it negative)?

1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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# Homework Help: Question about two circular concentric coils

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