MAGNETISM : MAGNETISM Magnet-a piece of material that has a concentrated magnetic field surrounding it.
-natural and artificial magnets
-permanent and temporary
Magnetism : Magnetism Magnets have a North and south pole.
Magnets align because of a fundamental law of magnetism
“Like poles repel and unlike poles attract.”
Magnetism : Magnetism Lines of force-flux lines surround a magnet.
Magnetism : Magnetism Lines of force-flux lines surround a magnet.
Electricity and Magnetism : Electricity and Magnetism Electricity creates magnetism in non-magnetic substances. Ie: copper.
Magnetism can create electricity in non-magnetic substances.
Lines of Force : Lines of Force Magnetic force lines are called flux lines. Travel from north to south pole of magnet.
Four rules for flux lines
Flux lines have polarity.
Lines form complete loops.
Flux lines can not cross
Lines form the smallest loops.
Current flow and Magnetism : Current flow and Magnetism Current flow in wire.
Left hand rule ie: example on board
Figure 9-7 page 172
Induction : Induction The effect that the magnet has on the iron bar without any physical contact between them.
The field of a charged body can affect another body without the two bodies actually touching.
Electromagnetic Induction : Electromagnetic Induction The action that causes electrons to flow in a conductor when the conductor moves across a magnetic field.
Motion is essential for E.I. Some outside force must be applied to the conductor to move it through the magnetic field.
Factors in Induction : Factors in Induction The strength of the magnetic field.
Speed of the conductor.
The angle the conductor cuts the field.
Length of the conductor in the field.
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Assignment : Assignment Questions 1-10 Page 180