The drawing shows a copper wire (negligible resistance) bent in a circular shape with a radius of .5 m. The radial section BC is fixed in place, while the copper bar AC sweeps around at an angular speed of 15 rad/s. The bar makes electrical contact with the wire at all times. The wire and bar have negligible resistance. A uniform magnetic field exists everywher, is perpendicular to the plane of the circle, and has a magnitude 3.8E-3T. Find the magnitude of the current induced in the loop ABC.(adsbygoogle = window.adsbygoogle || []).push({});

http://edugen.wiley.com/edugen/courses/crs1000/art/qb/6e/ch22p_26.gif

I thought I had done this right but my answer comes out incorrect. I found the equation E=-NB(deltaA/deltaT) using Faraday's Law. I then went about finding the ratio delta A/ Delta T. I took delta A/pi x r^2 = delta t/delta T. This gave delta A/delta t = pi x r^2/T, which I then got wr^2/2 from, so I found that delta A / delta t = wr^2/2.

However, after plugging the numbers in, my answer was incorrect. I asked my instructor, and he said I was right there with the answer, but I'm not sure where else to go or if I need to use different figures since we're using rad/s for the angular velocity. Any help here at all is appreciated.

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# Homework Help: Faraday's Law Help?

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