On this day in physics: 26 January 1911 Happy Birthday to Polykarp Kusch, Nobel Prize winning physicist who shared the prize in 1955 with Willis Lamb. The Nobel Prize in Physics 1955 was divided equally between Willis Eugene Lamb "for his discoveries concerning the fine structure of the hydrogen spectrum" and Polykarp Kusch "for his precision determination of the magnetic moment of the electron" [Source].
Word of the Day: Magnetic Moment is related to the amount of torque generated by an object in the presence of a magnetic field. If you're a totally electrically neutral object, you're moment is 0. Neutrons, for example, will travel through a magnetic field as if it wasn't there. Now, if you're something like an electron, or a planet, or a charged atom, or a current carrying wire, the situation is slightly different. It can be thought of as a vector, or an arrow of a specified length and direction, for any given item that you are considering. For the extremely small, like electrons studied by our birthday boy Polykarp, the magnetic moment is dependent on the particle's spin and some constants, notably planck's constant, and the Bohr Magneton (maybe future words of the day? tweets please). For something like a current carrying wire, it's related to the diameter of the wire, as well as the current travelling through the wire. This magnetic moment is important because the overall magnetic properties of a material are highly dependant on the magnetic moments of their component atoms. Anything that you see in everyday life that deals with magnets, i.e. the ones that stick to your fridge, the ones in your speakers, etc. are behaving this way because of the component magnetic moments of the atoms which make up the materials (mostly ferromagnetism.)
Killer Resource: Motion of a Charged Particle in a Magnetic Field.
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Keywords: Magnetic, Moment, Charged, Particle, Electron
