Question

induced emf when ring is rotating about its diameter in uniform magnetic field

Answer 1

torque acting on the dipole in uniform magnetic field is given by:τ=mBsinθwhere m is the magnetic momentB is the magnetic fieldand θ is the angle between m and B.work done in rotating the dipole from θ1 to θ2 magnetic field is given by:w=∫θ1θ2τdθ=∫θ1θ2mBsinθdθ=-mBcosθθ1θ2=-mBcosθ2-cosθ1w=mBcosθ1-cosθ2if θ1=90 degree and θ2=θthenw=mB0-cosθw=-mBcosθ=-m.→B→this work done will be stored as potential energy of the dipole.U= -m.→B→

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