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

A coil with 253 turns of wire, a total resistance of28 Ohms, and a cross-section area of 0.36m^2 is positioned in a plane perpendicular to the field of a powerful electromagnet.

What average current is induced in the coil during the 0.33s that the magnetic field drops from 2.2T to 0.0T? Answer in units of A.

2. Relevant equations

E = BA / t

V = IR

3. The attempt at a solution

EMF = Change in B * Area / time

= (2.2 * .36) / .33

I plug that into V = IR

V = IR

[(2.2 * .36) / .33] = I * 28 Ohms

I = [(2.2 * .36) / .33] / 28 =0.0857142857A

However I get the wrong answer.

I think it has something to do with the 253 coils of wire but I'm not sure.

Any help is appreciated.

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# Induced EMF, finding current

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