Physics-
General
Easy
Question
A circular metal plate of radius 
is rotating with a uniform angular velocity
with its plane perpendicular to a uniform magnetic field B. Then the emf developed between the centre and the rim of the plate is
The correct answer is:
From Faraday’s law of electromagnetic induction, the emf induced between center and rim is equal to rate of change of magnetic flux.
Where, 
where 
is magnetic field and 
the area.
Also, 
where 
is periodic time,
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