 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
 |
| • |
Imagine
a charge travelling circularily
|
|
|
about
an axis builds up a magnetic
|
|
|
moment
|
|
|
| • |
It
rotates (spins) about its own axis (the
|
|
|
blue
arrow) and precesses about the axis
|
|
of
the magnetic field B (the red arrow).
|
|
|
The
frequency of the precession (w) is
|
|
|
proportional
to the strength of the
|
|
|
magnetic
field:
|
|
|
| • |
w = g B0
|
|
|
|
|
| g |
=
magnetogyro ratio
|
|
|
Magnetic field mrasured in Tesla
|
|
|
1 T = 10,000 gauss
|
|