MCQ
A rectangular coil $ABCD$ is rotated anticlockwise with a uniform angular velocity about the axis shown in diagram below. The axis of rotation of the coil as well as the magnetic field $B$ are horizontal. The induced $e.m.f$. in the coil would be maximum when
  • The plane of the coil is horizontal
  • B
    The plane of the coil makes an angle of $45^o$ with the magnetic field
  • C
    The plane of the coil is at right angles to the magnetic field
  • D
    The plane of the coil makes an angle of $30^o$ with the magnetic field

Answer

Correct option: A.
The plane of the coil is horizontal
a
(a) Emf = $e = {e_0}\sin \theta ;$ e will be maximum when $\theta$ is $90^o$ i.$e$. plane of the coil will be horizontal.

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