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Q.
In the question number $73$, for the coil given the magnetic moment is
Moving Charges and Magnetism
Solution:
The magnetic moment is given by
$m=NIA$
$=NI \pi r^{2}=100 \times 3.2 \times 3.14 \times (10 \times 10^{-2})^{2}$
$=100 \times 3.2 \times 3.14 \times 10^{-2}$
$=10 \, A\, m^{2}$