18. The Effect of Magnetism on Water
Dave, I am studying magnets and was reading your site and came across the
"Short electromagnetic waves carry enough energy to eject electrons from
matter, in particular ultra-violet light and x-rays. A near-vacuum is
necessary for any such procedure to be effective, because in ordinary air
free electrons collide with molecules, lose their energy and are recaptured.
In most of space however matter is so rarefied and encounters are so few
that free electrons persist for a long time."
"When one or more electrons are torn off an atom, the remaining atom becomes
positively charged and is known as a positive ion. Positive ions carry most
of the energy and electrical current in the magnetosphere, and are the main
component of both the inner and the outer radiation belts. Fast ions are
also produced by the Sun as a continuous outflow in all directions, known as
the solar wind, which initiates and powers magnetic storms and similar
The simplest atom is the one of hydrogen, with just one electron. Tearing
off that electron gives the simplest ion, the proton. The proton has a close
relative, the neutron--nearly the same mass, but no electric charge--and
together these two form the basic building blocks from which the nuclei of
all atoms are constructed.
Most of the fast ions in the magnetosphere and in the solar wind are protons. In the ionosphere one would expect to see ions of oxygen or
nitrogen, the main atmospheric gases, and in fact most ions there are O+,
oxygen atoms which have lost one electron (out of eight). Some O+ ions end
up in the radiation belt, greatly energized by magnetic storms."
Which leads to my question. . .
What effect would a magnet have on H2O, e.g. if you put a magnet in a glass of water, what happens to the water molecule, does it lose any electrons? What about any minerals that might be in the water?
Thanks in advance.
If you put a magnet in a glass of water ... it will get wet, for sure. Electomagnetic effects are a bit more elusive, because magnetism
affects only (1) magnets or (2) electric currents. Electric charge by
itself responds to electric fields (voltage differences), which is
something else. Let me stick here to magnetic forces.
Each proton is a tiny magnet, as is an electron, so
a magnet will exert a small force on them. It will be like that of
the Earth's field on a compass needle, namely it will try to turn them
around to some preferred direction, but will not attract them anywhere.
Very little energy is involved. However, if your magnetic field oscillates
(as does the one of a radio wave, say), the proton will try to swing back
and forth rapidly, and if the frequency of the wave resonates with the
natural frequency at which the tiny protonic magnet oscillates, the proton can
absorb energy (and scatter it away, too). That is the basis of Magnetic
Resonance Imaging (MRI) in medicine, and of the proton precession
magnetometewr (and the more recent Overhauser magnetometer) used by
scientists. I wrote a bit about it in
Somehow this does not look like what you had in mind!
If you pass an electric current through water in the presence of a
magnetic field, its flow will be pushed aside. That force--it's a force on an electric current, the water is just incidental--can be used to pump water, but it is an inefficient method, because an electric current
in water wastes energy and promotes corrosion. However, in "fast breeder"
nuclear reactors, such as "Superphenix" in France, liquid sodium is
used as coolant, and is pumped by "electromagnetic pumps" based on this
principle. In such a reactor ("fast" refers to the type of neutrons used,
not to the reactor) heat is generated by fission in a rather small volume,
maybe a meter (3 ft) across, and since the heating rate is very high, it
must be removed quickly. Liquid sodium is a good coolant, since it conducts
heat very well, and it conducts electricity well, with small wastage. Unfortunately it is also tricky to handle and will burn when exposed to air. In 1990 Superphenix was shut down because of leaks
of its coolant, and it has only operated intermittedly since then. See:
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