A charge $q$ is spread uniformly over an insulated loop of radius $r$ . If it is rotated with an angular velocity $\omega $ with respect to normal axis then the magnetic moment of the loop is
A$\frac{1}{2}\,\,q\omega {r^2}$
B$\frac{4}{3}\,\,q\omega {r^2}$
C$\frac{3}{2}\,\,q\omega {r^2}$
D$q\omega {r^2}$
JEE MAIN 2018, Medium
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A$\frac{1}{2}\,\,q\omega {r^2}$
a Magnetic moment, $\mu \, = \,IA\, = \,\frac{{qv}}{{2\pi r}}(\pi {r^2})$
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