Charge Q is uniformly distributed on a thin insulating ring of mass m – McqOptions

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1.	Charge Q is uniformly distributed on a thin insulating ring of mass m which is initially at rest. To what angular velocity will the ring be accelerated when a magnetic field B, perpendicular to the plane of the ring, is switched on?
A.	\[\frac{QB}{2m}\]
B.	\[\frac{3QB}{2m}\]
C.	\[\frac{QB}{m}\]
D.	\[\frac{QB}{4m}\]
Answer» B. \[\frac{3QB}{2m}\]

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