ElectroMagnetic InductionMedium
Question
A non conducting ring of radius R and mass m having charge q uniformly distributed over its circumference is placed on a rough horizontal surface. A vertical time varying uniform magnetic field B = 4t2 is switched on at time t = 0. The coefficient of friction between the ring and the table, if the ring starts rotating at t = 2 sec, is :


Options
A.
B.
C.
D.
Solution
E × 2πR = πR2
E =
(qE)R = (μmg) R
μ =
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