Solenoids – Physics coursework

Solenoids Permanent Magnet- Magnetic Field.http//www.diracdelta.co.uk/science/ root word/m/a/ magnetized%20 guinea pig/source.html Magnets have two poles called North and South.Similar (like) bewitchd poles repel. Unlike magnetized poles attract. A magnet attracts a piece of iron. The roughly important of the two properties of attraction and repulsion is repulsion. The only way to posit if an object is magnetised is to see if it repels another magnetised object. The strength and care of a magnetic champaign is represented by magnetic field profligates. Field casts by convention go from North to South. A magnetic field is three-dimensional, although this is not often seen on a drawing of magnetic field lines.Electromagnets A magnetic field exists around all wires carrying a current. When there is no current the compass needles in the diagram shown line up with the Earths magnetic field. A current through and through the wire produces a circular magnetic field. See what happe ns when there is a current in the wire. The magnetic field for a volute of wire is shown below. The magnetic palm from each of the turns in the coil add together, so the total magnetic field is much stronger. This produces a field which is similar to that of a patty magnet. A coil of wire like this is often called a solenoid.http//www.bbc.co.uk/bite surface/ prototype/physics/using_electricity/movement_from_electricity/revision/1/slideshow-1/2/An electromagnet consists of a coil of wine, through which a current can be passed, wrapped around a soft iron core. This core of magnetic material increases the strength of the field due to the coil. Soft iron is easily magnetised, and easy to demagnetise- it does not check its magnetism after the current is switched off. Steel, on the other hand, is hard to magnetise and demagnetise, and so it retains in magnetism. It is used for permanent magnets. The strength of an electromagnet depends onThe size of the current flowing through the coi l The number of turns in the coil The material inside of the coil Heinmann physics Dobrinys http//hyperphysics.phy-astr.gsu.edu/hbase/solids/ferro.htmlc4Ferromagnetic materials exhibit a long ordering phenomenon at the atomic level which causes the unpaired electron spins to line up parallel with each other in a theatrical role called a domain. Within the domain, the magnetic field is intense, but in a bulk sample the material will usually be unmagnetized because the galore(postnominal) domains will themselves be randomly oriented with respect to one another. The main implication of the domains is that there is already a high degree of magnetic induction in ferromagnetic materials within individual domains, but that in the absence of external magnetic fields those domains are randomly oriented. A low applied magnetic field can cause a bighearted degree of alignment of the magnetic moments with the external field, giving a large multiplication of the applied field.Ferromagnet ismIron, nickel, cobalt and some of the rare earths (gadolinium, dysprosium) exhibit a unique magnetic behavior which is called ferromagnetism because iron (ferrum in Latin) is the most earthy and most dramatic example.