Magnetism Lec4 PDF

MAGNETISM LEC4 MIDTERMS MAGNETISM - A fundamental property or some Ferromagnetic - Can be strongly magnetized. forms of matter which have the ability to attract Examples are ALUMINUM, NICKEL and COBALT. iro...

MAGNETISM LEC4 MIDTERMS MAGNETISM - A fundamental property or some Ferromagnetic - Can be strongly magnetized. forms of matter which have the ability to attract Examples are ALUMINUM, NICKEL and COBALT. iron. Paramagnetic - Weakly attracted to both poles - An electric charge spinning on its own axis (in of the magnetic fields. Ex. GADOLINIUM motion) will create a magnetic field (𝐵_0). Diamagnetic - Weakly repelled by both poles of a magnetic field. Examples are WATER and PLASTIC. The lines of a magnetic field are always closed loops. Such a field is called bipolar or dipolar, it always has a north and a south pole Magnetic Susceptibility - The degree to which a material can be magnetized. MAGNETIC PERMEABILITY 0 Is the ability of a material to attract the MAGNETIC LAWS lines of magnetic field intensity. 0 Like magnetic poles repel, unlike 0 In a ferromagnetic material, the magnetic poles attract. Like magnetic magnetic dipoles are randomly oriented poles repel, unlike magnetic poles but this changes when the dipoles are attract. brought under the influence of an 0 The magnetic force of external magnetic field. attraction/repulsion is proportional to the product of magnetic pole strengths divided by the square of the distance between them (Gauss Law) Naturally occurring magnets 0 There is no smallest unit of magnetism. - Earth, lodestones Artificially induced permanent magnets ELECTROMAGNETISM - Horseshoe magnet, bar magnet 0 Electricity and magnetism are Electromagnets intimately connected. They are both different aspect of the same basic - Consist of a wire wrap around an iron force- Electromagnetic force core. When an electric current is conducted through the wire, a magnetic field is created. - Luigi Galvani - Alessandro Volta Voltaic pile Nonmagnetic - Unaffected by a magnetic field. - Hans Oersted Examples are WOOD and GLASS Electricity and induce a magnetic field. MAGNETISM LEC4 MIDTERMS 0 The direction of the magnetic field around the wire can be determined by using the right hand rule 0 A coil of wire is called a solenoid. 0 The magnitude of the induced current depends on four factors: 1. The strength of the magnetic field 2. The velocity of the magnetic field as it moves past the conductor 3. The angle of the conductor to the magnetic field 4. The number of turns in the conductor Electric Generator - Converts mechanical energy to electrical energy (mechanical motion produces electric current) Electric Motor - Electric current produces mechanical motion Induction Motor - Motor used in x-ray tubes - Powers the rotating anode