Download Bar magnet

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A magnet attracts certain materials … Iron Steel Cobalt Nickel
2 A bar magnet is strongest at each end Magnetic Poles
3 A suspended magnet points approximately North ­ South Com p
ass
North­seeking pole South­seeking pole Magnetic poles exist in pairs … Equal strength 4 Like poles repel Unlike poles attract
5 Induced Magnetism
6 Iron and Steel Iron Magnetically soft
Easy to magnetise Loses its magnetism easily Steel Magnetically hard More difficult to magnetise Better at keeping its magnetism 7 A region where there is a force on a moving charge. (A region where magnetic forces can be felt.) Direction … Plotting compass
8 A line that shows the direction of the force on a north pole Point north to south
The tangent to the line shows the direction of the magnetic field 9 To Plot The Magnetic Field Due To A Bar Magnet Dots
10 To Plot The Magnetic Field Due To A Bar Magnet
or Use iron filings 11 Horse­Shoe Magnet Earth’s Magnetic Field
12 Demo 1819 Han Christian Oersted Large current // Resistor
13 Battery
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Poles ?? Magnetic Field Coil > Loop
16 Similar to …
17 Battery etc. …
18 Solenoid + soft iron core Current on … Current off … Uses Scrapyards Electric motors Electromagnetic relays
19 Ø “Bar magnet” Ø Electric currents … Ø Mag. Declination (Mag. Variation) Ø Angle of dip Ø Navigation
20 Earth’s Magnetic Field Magnetic Declination Magnetic Dip
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