(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known dataDuring a 65 ms interval, a change in the current in a primary coil occurs. This change leads to the appearance of a 6.0 mA current in a nearby secondary coil. The secondary coil is part of a circuit in which the resistance is 12 . The mutual inductance between the two coils is 3.1 mH. What is the magnitude of the change in the primary current?

2. Relevant equations

mutual inductance: M = (number of loops in coil 2 * flux through coil 2)/ current of coil 1

Faradays law

emf = -M x (change in voltage of coil 1/change in time)

3. The attempt at a solution

i could use faraday's law to solve for change in current of coil 1, but i dont know what the emf is.

i know the formula for emf is vBL, but i dont know v, B, or L!!!

i cant use the mutual inductance formula because i dont know the # of loops in coil 2.

If someone could please point me in the right direction here i would greatly appreciate it.

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

2. Relevant equations

3. The attempt at a solution

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# Mutual Inductance (ouch, my brain)

Can you offer guidance or do you also need help?

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