A Flat Circular Loop of Wire of Radius $0.50 \mathrm {~m}$

Multiple Choice

A flat circular loop of wire of radius $0.50 \mathrm {~m}$ that is carrying a $2.0$ -A current is in a uniform magnetic field of $0.30 \mathrm {~T}$ . What is the magnitude of the magnetic torque on the loop when the plane of its area is perpendicular to the magnetic field?

A) $0.41 \mathrm {~N} \cdot \mathrm { m }$
B) $0.58 \mathrm {~N} \cdot \mathrm { m }$
C) $0.47 \mathrm {~N} \cdot \mathrm { m }$
D) $0.52 \mathrm {~N} \cdot \mathrm { m }$
E) $0.00 \mathrm {~N} \cdot \mathrm { m }$