A closely wound, retangular coil of 80 turns has dimensions of .25m x .4 m. The plane of the coil is rotated, in .06 sec from a position where it makes an angle of 37 degrees with a magnetic field of 1.1T to a position perpendicular to the field. What is the average emf induced in the coil?(adsbygoogle = window.adsbygoogle || []).push({});

Here's what I came up with:

In .06 sec, the coil moves 53 degrees(90 - 37). So, I converted this to raidians, which is .925025 rad. It moves this far in .06 sec, so it's rotational speed is 15.42 rad/sec.

[tex] |E| = NwBA|Sin Wt|[/tex]

My book states that to find the average emf, replace Sin(wt) with the average value. They did this and came up with [tex]2/\pi[/tex]

So, the average value of [tex] E = 2NwBA/\pi[/tex]

Plugging into the equation, I get 86.39Volts, far from the 58.4 Volts answer. Can anyone tell me what I'm doing wrong? Thanks.

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# Homework Help: Faraday's Law and coil EMF

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