Magnets and Electromagnetism


Georgia Performance Standards

SPS10. Students will investigate the properties of electricity and magnetism.

c. Investigate applications of magnetism and/or its relationship to the movement of electrical charge as it relates to

•  electromagnets

•  simple motors

•  permanent magnets

MAGNETS:

How were magnets discovered?

•  Magnetite/or ______= naturally occurring mineral

•  Could pick up metallic objects

•  If floated on water, it would always orient itself in the same direction

The Magnetic Force…

•  Is an interaction between two ______

•  can even be felt before magnets touch

•  gets ______as the magnets get closer

What is a magnetic field?

•  a field that

o  surrounds a magnet and exerts magnetic force

o  connects the ______of a magnet together

How do magnets interact?

•  ______poles (N,S) attract each other

•  ______poles (N, N or S,S) repel each other

What makes something magnetic?

•  Magnetic domain = groups of ______with aligned magnetic poles

n  unaligned magnetic domains = Magnetic or Not Magnetic?

______

n  aligned magnetic domains= Magnetic or Not Magnetic?

______

How can magnets be “demagnetized?”

1. ______

2. ______

•  both cause the magnetic domains to move around and become unaligned

What happens when you cut a magnet into two pieces?

S N

break in two

S N S N

ELECTROMAGNETS:

Interaction between magnetism and electricity

•  Magnetism can be produced by electricity

•  Electricity can be produced by magnetism

What is an electromagnet?

•  ______magnet made by placing a piece of metal inside a

______-______wire

•  Temporarily aligns magnetic domains

What are some ways electromagnets are used?

1. ______

2. ______

3. ______

4. ______

5. ______

How can the strength of an electromagnet be increased?

•  add more ______

•  increase the ______through the wire

Benefits of Electromagnets (versus Permanent Magnets)

1.  ______

2.  Can control the strength

Electromagnetic Induction