Question

An MRI technician moves his hand from a region of very low magnetic field strength into an MRI scanner's 2.00 T field with his fingers pointing in the direction of the field. His wedding ring has a diameter of 2.5 cm and it takes 0.45 s to move it into the field. What average current is induced in the ring in A if its resistance is 0.0100 Ω ?

Answer 1

Answer:

2.62 A

Explanation:

B = 2 T, Diameter = 2.5 cm , radius, r = 0.0125 m, t = 0.45 s, r = 0.01 ohm

Induced emf, e = rate of change of magnetic flux

e = A x dB / dt = 3.14 x (0.0125)^2 x 2 / 0.45

e = 0.026 V

induced current, i = e / R = 0.026 / 0.01 = 2.62 A