Download Magnets

How are these guys related to electricity?
Magnetism Unit Vocabulary
1.
Magnet

Definition- Materials that attract iron or contain iron.
Sentence- I used a magnet to pick up a nail.
Magnetic Fields
3. Electromagnets
4. Solenoid
5. Generator
6. Motor
2.
BrainPop 1 – Magnetism

video
Iron Triad
Properties of Magnets- Activity 1

Using the paperclips at your station, try to
find out where the magnet is strongest:
North Pole, South Pole, or in the middle.
Properties of Magnets- Activity 2

Place the North and South poles in the
positions you see them in here. What
happened? Why?
I don’t get it. How does a magnet work?

Magnets work by causing electrons to move
and this movement creates a magnetic field
and electricity.

In iron, nickel, and cobalt, the atoms group
together (domains) and line up by poles.

Most materials, the magnetic fields of
individual atoms cancel each other out.
Properties of Magnets
 Two poles (strongest part)
N
S
Properties of Magnetst
 Exert forces
○ Can push or pull
movement
N
S
N
S
Properties of Magnets
 Surrounded by a magnetic field
○ A magnetic field is the area around
the magnet where magnetic forces
act.
Properties of Magnets
 Magnetic fields can produce
electrical current in conductors.
Opposite is true too.
 Electricity can produce a magnetic
field.
Compare w/ Electricity (Very Similar)
Opposites attract/ like
repels.
 Both depend on electrons.
 Moving electrons (current)
produce magnetic fields,
so electricity can generate
a magnetic field.
 A magnetic field can
generate an electric
current.

What materials are magnetic?
What materials
are magnetic?
Types of Magnets
Ferromagnets
 Electromagnets
 Temporary magnets
 Permanent magnets

What is the largest magnet you
have ever seen?
BrainPop 2 - compass

video
Poles on a Compass- Activity 4
Which pole of the magnet do you think
the compass will point to?
 Place your compass on the bar magnet.
 Which pole did it point to? Why?
 How does a compass work?

BrainPop 3
Electromagnets are TEMPORARY!
http://en.wikipedia.org/wiki/File:Electromagnet.gif
Electromagnets
Temporary
 Lose magnetism when electric current (I ) is
removed.
 Contain 3 parts (usually):

 Iron core (can you make it without this? Activity 4)
 Solenoid (coiled wire that produces a magnetic
field when current runs through it)
○ More coils means what?
 Source
○ More volts means what?
BrainPop 4
Oersted’s Experiment- Activity 5

Turn to p. 462
and try to
duplicate the
Oersted’s
experiment in
Figure 13 a,
b, and c.
Check with
me after each
one.
Magnetic Force & Electric Current
Activity 6- See if you can duplicate the
force exerted on the wire when current
goes a runnin.
 Reference p.465 Figure 16 a & b.

Generators & Motors

Generators: A device that converts
mechanical energy into electrical energy.
 Most of the electrical energy we use comes
from generators.

Motors: A device that converts electrical
energy into mechanical energy that is
used to do work.
 Examples – blenders and washing machines