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Question
A flat coil of wire rotates at a constant speed about an axis perpendicular to a uniform magnetic field. Draw a graph to show how the induced e.m.f. varies relative to the positions of the coil during its one complete rotation. At what position of the coil, the e.m.f. has the maximum value?
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Solution
Figure below shows the variation in induced e.m.f. relative to various positions of coil, during its one complete rotation.
The e.m.f. is maximum when the coil is with its plane parallel to the magnetic field.
V = Coil vertical
H = Coil Horizontal
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