A 30-turn coil of diameter 2 cm carries a current of 10 mA. When it is placed in a uniform magnetic field of 0.05 T, the magnitude of the maximum torque that could be exerted on the coil by the magnetic field is
A. 1.88 × 10-5 N∙m
B. 4.7 × 10-6 N∙m
C. 4.7 × 10-7 N∙m
D. 1.88 × 10-8 N∙m.
Answer:B
A 30-turn coil of diameter 2 cm carries a current of 10 mA. When it is placed in a uniform magnetic field of 0.05 T, the magnitude of the maximum torque that could be exerted on the coil by the magnetic field is
A. 1.88 × 10-5 N∙m B. 4.7 × 10-6 N∙m C. 4.7 × 10-7 N∙m D. 1.88 × 10-8 N∙m.