electromagnetism notes 6-5.3

Slide 1: 

Magnetism is the force of ____________ or ___________ of magnetic materials. attraction repulsion Notes: Electromagnets

Slide 2: 

A __________ ______ is an area around a magnet that applies a force to magnetic materials without touching them. Notes: Electromagnets magnetic field

Slide 3: 

The magnetic field actually keeps going out forever, it just gets weaker the farther away from the magnet it is. It eventually gets too weak to move anything.

Notes: Electromagnets: 

Notes: Electromagnets Electromagnets An electromagnet is formed when a ________ in an electric circuit is wrapped around an _____ _____ producing a magnetic field. The magnet that results loses its magnetism if the electric current ______ ________ . Electric current is simply the flow of ______________ . (or the flow of charged particles, like electrons) wire iron core stops flowing electricity

Slide 5: 

Generators A generator changes ____________ energy into ___________ energy when a coil of wire is rotated near a magnet. mechanical electrical N S

Slide 6: 

Generators Generators at ______ _______ produce electric energy for our homes. Water, wind or steam pushes huge wheels called _________ . The turbines rotate _________ near coils of wire to make electricity. Smaller generators may be powered by __________ . power plants turbines magnets gasoline

Slide 7: 

Simple electric motors A motor changes ___________ energy into ____________ energy by rotating an electromagnet between _______ of a magnet. electrical mechanical poles N S

Slide 8: 

How it works: The coil of the electromagnet is connected to a source of ___________ . When electricity flows through the electromagnet, a ___________ field is produced. electricity magnetic S N N S

Slide 9: 

S N N S attract repel attract repel Like poles of the magnets _______ and unlike poles of the magnets _______ . This causes the coil to ___________ , changing electrical energy to mechanical energy. repel attract rotate Notice, there are four forces, all working to make the electromagnet spin in the same direction.

Slide 10: 

N S The electromagnet turns off when it comes close to the magnets because it loses its electrical connection. But it was already in motion, so it keeps spinning past the pole. Electromagnet turned off (north pole is gone) No longer connected to battery

Slide 11: 

N S N S After the electromagnet spins past the magnet its poles switch, because it gets an electrical connection with the other side of the battery Now these poles repel and the electromagnet is pushed away Electromagnet turned on with different pole (used to be north) Connected to positive side of battery (used to be negative)

Slide 12: 

N S This cycle repeats over and over. The poles keep switching and the electromagnet keeps getting pushed away from the magnets in the same direction.

Slide 13: 

N S The rotating coil of wire can be _________ to an object to make it _____. Examples: ________ on an electric car, ___ blades, a ______ ____. attached spin wheels fan

Slide 14: 

N S The rotating coil of wire can be _________ to an object to make it _____. Examples: ________ on an electric car, ___ blades, a ______ ____. attached spin wheels fan disco ball But, what good is a disco ball without lights or music?