Curses. I was expecting something novel from this thread.
Using film since before it was hip.
"One of the most singular characters of the hyposulphites, is the property their solutions possess of dissolving muriate of silver and retaining it in considerable quantity in permanent solution" — Sir John Frederick William Herschel, "On the Hyposulphurous Acid and its Compounds." The Edinburgh Philosophical Journal, Vol. 1 (8 Jan. 1819): 8-29. p. 11
What about a strong, alternating magnetic field such as that which might be generated by a rotating drum with magnets fixed to its surface in alternate N-S-N-S fashion?
You can use this technique to REPEL copper, aluminum and other non-ferromagnetic metals. It's the eddy currents which cause the repulsion.
This is how trash recycling machines separate ferromagnetic metals, non-ferromagnetic metals and paper/plastic/trash. First, they use a magnet to suck up the steel and iron. Then they use a rotating drum magnet to repel the copper, aluminum, etc. into a chute.
It is important not to confuse atoms with ions. Their magnetic properties are very different.
There are three types of magnetic susceptability; paramagnetism, diamagnetism, and ferromagnetism. The first two are extremely small and need special equipment to be measured. Most materials exhibit either paramagnetism or diamagnetism. A very few substances like iron exhibit ferromagnetism.
Last edited by Gerald C Koch; 07-14-2012 at 12:46 AM. Click to view previous post history.
A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.
Can light or radiation have an effect on ferromagnetism, to a degree that it could be utilized in some fashion to make an image? I'm kind of thinking along the lines of Xerox; where a charged plate of selenium loses that charge with light exposure. Any kind of similar phenomenon we can exploit with magnetism?