A circular coil having N turns and radius r carries a current I. It is held in the XZ plane in a magnetic field \(B\hat i\). The torque on the coil due to the magnetic field is:

\(\frac{{{\rm{B}}\pi {{\rm{r}}^2}{\rm{I}}}}{{\rm{N}}}\)

\(\frac{{{\rm{B}}{{\rm{r}}^2}{\rm{I}}}}{{\pi {\rm{N}}}}\)

A circular coil having N turns and radius r carries a current I. It is

1.	A circular coil having N turns and radius r carries a current I. It is held in the XZ plane in a magnetic field \(B\hat i\). The torque on the coil due to the magnetic field is:
A.	\(\frac{{{\rm{B}}{{\rm{r}}^2}{\rm{I}}}}{{\pi {\rm{N}}}}\)
B.	Bπr2 IN
C.	\(\frac{{{\rm{B}}\pi {{\rm{r}}^2}{\rm{I}}}}{{\rm{N}}}\)
D.	Zero
Answer» C. \(\frac{{{\rm{B}}\pi {{\rm{r}}^2}{\rm{I}}}}{{\rm{N}}}\)

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A circular coil having N turns and radius r carries a current I. It is held in the XZ plane in a magnetic field \(B\hat i\). The torque on the coil due to the magnetic field is:

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