Question

In what plane would a flat surface coil NOT receive MRI signal and why? Which of Maxwell’s laws is relevant here? Assume the coil lies flat on the scanner bed, the z-direction is parallel to the magnet bore, the x-direction is horizontal, and y-direction is vertical.

Answer 1

MRI signal is the electric signal that get induced in the coil whenever the magnetic flux through coil changes.flux changes whenever there is relative motion between magnetic field of magnet and the conduction coil.as the coil lies flat on bed it is in the xz plane.y direction will be vertical.magnetic field is in the z direction.relative motion of conducting coil must be perpendicular to magnetic field to change the magnetic flux and to generate induction current is coil.on moving the magnet in xy plane z component does not changes.so flux will be constant,and there will be no induction current in the coil.so on xy plane coil will not recieve mri signal.the induction of current on changing magnetic flux is faradays law,which is maxwells third equation of electromagnetism theory...curl of E=-dB/dt

Where E is electric field that get induced in coil,B is magnetic field and d/dt is change in magnetic field with time.