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Question
Show diagrammatically how an alternating emf is generated by a loop of wire rotating in a magnetic field. Write the expression for the instantaneous value of the emf induced in the rotating loop.
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Solution
Generation of an alternating e.m.f. by a loop of wire rotating in a magnetic field
Expression of the instantaneous value of the induced e.m.f. in a rotating loop
ε = NBAω sinωt
Where N = number of turns in armature coil
B = Magnetic field vector
A =Area vector of the coil
ω = Angular speed
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