A circular loop with radius a = 0.25 m and N = 17 turns lies in the plane of the page (x-y plane). The wire used in constructing the loop has a resistance per unit length of dR/dl = 0.11 W/m.(adsbygoogle = window.adsbygoogle || []).push({});

A spatially uniform magnetic field points in the -z direction (into the page). In the interval between t = 0 and 15 s, the strength of this field varies according to the expression B(t) = 0.01 t^3 T/s3.

Calculate the current in the windings at t = 8 s. (Give the magnitude and algebraic sign - let a current that is clockwise in the view shown in the figure defined to be positive.)

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First, I calculated the B-field @ t=8, which turned out to be 6.408849013 V.

Now, to find the current, I'm advised to write the equivalent Kirchoff's loop equation. I'm having a hard time doing this, because I'm given dR/dI, instead of just R. Since it's "resistance per unit length", I multiplied by 2pi*RN. What happens then?

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# Homework Help: Loop in a B-Field

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