A circular coil (radius = 0.40 m) has 160 turns and is in a uniform magnetic field. When the orientation of the coil is varied through all possible positions, the maximum torque on the coil by magnetic forces is 0.16 N ? m when the current in the coil is 4.0 mA. What is the magnitude of the magnetic field?

A. 0.37 T
B. 1.6 T
C. 0.50 T
D. 1.2 T
E. 2.5 T


Answer: C

Physics & Space Science

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