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A pair of thin coaxial coils A and B, of radii a and b, and with
and
turns, respectively are separated by a distance L. Show that, if b<<a the mutual inductance is
What is the magnetic dipole moment of coil B when a current
flows in it?
In a simple nuclear magnetic resonance experiment, atoms confined to a small sample chamber each possess a magnetic dipole moment of fixed magnitude
whose direction precesses about the z-axis at angular frequency
, at constant angle
to that axis. At a distance
from the sample chamber is a single-turn coil of radius a, with its axis on the x-axis. Write down an expression for the Cartesian components of the magnetic dipole moment of an atom at time t. Derive an expression for the r.m.s. voltage per atom induced in the coil.
In an experiment to map the human lungs, nuclear magnetic resonance is performed on xenon gas that is inhaled by a subject. Each xenon nucleus has a magnetic dipole moment of magnitude
and precesses at a frequency of 400kHz. Stating carefully any assumptions you made, estimate the smallest volume of gas that could be detected by a single-turn coil with a voltage sensitivity of
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