t ypes of magnets permanent temporary electromagnets
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TYPES OF MAGNETS• Permanent• Temporary• Electromagnets
MAGNETAn object that attracts certain materialsIron and steel
MAGNETSMagnetism: force exerted by a magnet
Magnetic Poles: part of magnet where force is strongestEvery magnet has 2 poles (North & South)
Opposites attractLike repelBreak a magnet = 2 new magnets
MAGNETSMagnetic field: region around magnet in which magnet exerts forceMagnetic field lines
MAGNETSMagnetic domain: group of atoms whose magnetic fields are aligned
MAGNETSPermanent and temporary magnetsDropExpose to high temperatures
Earth: magnetic field
ELECTROMAGNETISMMagnetism that results from an electric currentCharge particle---electron---moves and creates a magnetic field
List 3 ways that the strength of an electromagnet can be controlled.
What are the 2 benefits of an electromagnet?
ELECTROMAGNETMagnet made by placing a piece of iron or steel (ferromagnetic core) inside a coil of wire
ELECTROMAGNET
ELECTROMAGNETCan be turned off and onCan control the strength of the magnet
Voltage source (increase = increase strength)
# times coil is wrapped around the core (increase # = increase strength)
How close together the coils are (closer = increase strength)
Size of ferromagnetic core (increase size = increase strength)
MAGNETS--CURRENT Magnets can be used to generate
electric current.Generator: a device that converts
the energy of motion (kinetic energy) into electrical energy
Shaft of generator turnsRotation of shaft causes coils of wire
to spin---creates a magnetic fieldCoils cross magnetic field line-----
electric current created
MAGNETS--CURRENTDirect current
Electric charge flows in ONE direction
Produced by batteriesAlternating current
Flow of electric charge that reverses direction at regular intervals
Home and school
MAGNETS--CURRENTTransformer
A device that increase or decreases voltage
Use magnetism to control the amount of voltage
Consists of 2 coils of wire wrapped around an iron ring
MAGNETS--CURRENT
WattUnit of measurement for power