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A plastic disc of radius $R$ has a charge $q$ uniformly distributed over its surface. If the disc is rotated at an angular frequency $\omega$ about it axis, the induction at the center of the disc is :-
  • A$\frac{{{\mu _0}q}}{{2\pi R}}$
  • B$\frac{{{\mu _0}\omega q}}{{2\pi R}}$
  • C$\frac{{{\mu _0}(2\pi q)}}{{\omega R}}$
  • D$\frac{{{\mu _0}\omega q}}{{2\pi }}$
Diffcult
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