jeffquitney
patreon
A Magnet Laboratory 1959 Physical Science Study Committee (PSSC) - MIT; Francis Bitter
🕑 Added 2020-01-29 21:29:05 +0000 UTCmore at http://quickfound.net/
'Six researchers in a lab at MIT in the late 1950's show-off the power of electro-magnets, and in the process, accidentally set an experiment on fire... Bitter is an important historical figure, whose degaussing techniques spared many an allied vessel from destruction by magnetic underwater mines during WWII. The generator shown was from Pittsbugh's street car system, relocated to MIT for use in Bitter's lab.'
Originally a public domain film, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied.
The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original).
https://en.wikipedia.org/wiki/Electromagnet
Wikipedia license: http://creativecommons.org/licenses/by-sa/3.0/
An electromagnet is a type of magnet in which the magnetic field is produced by an electric current. Electromagnets usually consist of wire wound into a coil. A current through the wire creates a magnetic field which is concentrated in the hole, denoting the centre of the coil. The magnetic field disappears when the current is turned off. The wire turns are often wound around a magnetic core made from a ferromagnetic or ferrimagnetic material such as iron; the magnetic core concentrates the magnetic flux and makes a more powerful magnet.
The main advantage of an electromagnet over a permanent magnet is that the magnetic field can be quickly changed by controlling the amount of electric current in the winding. However, unlike a permanent magnet that needs no power, an electromagnet requires a continuous supply of current to maintain the magnetic field.
Electromagnets are widely used as components of other electrical devices, such as motors, generators, electromechanical solenoids, relays, loudspeakers, hard disks, MRI machines, scientific instruments, and magnetic separation equipment. Electromagnets are also employed in industry for picking up and moving heavy iron objects such as scrap iron and steel...
https://en.wikipedia.org/wiki/Francis_Bitter
Francis Bitter (July 22, 1902 – July 26, 1967) was an American physicist.
Bitter invented the Bitter plate used in resistive magnets (also called Bitter electromagnets). He also developed the water cooling method inherent to the design of Bitter magnets. Prior to this development, there was no way to cool electromagnets, limiting their maximum flux density...
Bitter entered the University of Chicago in 1919... and received a Ph.D. at Columbia in 1928. At Columbia, Bitter began his lifelong fascination with magnets.
Career
Under a National Research Council fellowship, Bitter studied gases at Caltech with Robert Andrews Millikan, from 1928 to 1930. While at Caltech, he married Alice Coomara. She had been a moderately successful singer working under the stage name Ratan Devi.
In 1930, Bitter went to work for Westinghouse...
With a Guggenheim Fellowship, Bitter travelled to England in 1933 and worked at the Cavendish Laboratory at Cambridge University. There, he worked with Peter Kapitza on pulsed magnetic fields.
The following year, Bitter returned to America and his work at Westinghouse...
At M.I.T.
Bitter joined the Department of Mining and Metallurgy as an associate professor in 1934...
While at MIT, he developed the Bitter electromagnet which was/is the most powerful electromagnet design. He established a magnet laboratory in 1938, where he built a solenoid magnet that produced a constant field of 100,000 gauss (10 teslas).
He also did work in the first characterization of the Zeeman effect with George Harrison.
During the Second World War, Bitter worked for the Naval Bureau of Ordnance. He often traveled to England to find ways to demagnetize British ships to protect them from a new type of German mine, which used a compass needle to trigger detonation. The mine, dropped from the air, would sink to the bottom of a river and remain there with its magnetic needle aligned to the Earth's magnetic field at that location. When a ship passed over it, the mass of the ship caused the magnetic needle to move slightly. The movement was enough to detonate the mine. In his autobiography Magnets, the Education of a Physicist, he referred to this unique work as "Degaussing the fleet". (It is possible that he worked with Francis Crick, who was researching the same problem.)
After the war, Bitter returned to MIT and joined the faculty of the physics department. He became a full professor in 1951, and from 1956 to 1960, he served as associate dean of MIT's school of science. From 1962 to 1965, Bitter was the housemaster of Ashdown House, MIT's graduate dormitory...
