A patient is having a magnetic resonance imaging scan (an MRI) and has neglected

Question

A patient is having a magnetic resonance imaging scan (an MRI) and has neglected to remove a circular, metallic bracelet. The resistance of the bracelet is 0.00990 . The magnetic field within the MRI's solenoid is perpendicular to the opening of her bracelet. While taking the scan, the magnetic field decreases from 1.32 T to 0.45 T in 1.50 seconds. If the magnitude of the average induced current in the bracelet during this time interval is 0.2894 A, what is the area of the opening of the circular bracelet?

Explanation / Answer

Let A be the area.

emf induction :

= -A dB/dt

= -A * (0.45 - 1.32)/1.50 = 0.58*A volts ------- (1)

Also, using the relation:

i = /R

=> = iR = 0.2894* 0.00990 = 2.865*10^-3 volts ------- (2)

Equating (1) and (2), we get:

0.58*A = 2.865*10^-3

=> A = (2.865*10^-3)/0.58

= 4.94 x 10^-3 m2

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.