1. Electricity and Magnets
Introduction to Electronics
Electricity and Magnets
February 3rd 2012

2. Objectives Use the Internet to find a definition for electricity
What word describes the properties and interactions of magnets
What term refers to the magnetic field lines created by magnets
Complete a sketch of a magnet, the north and south poles and the magnetic field lines
Describe the relationship between unlike poles on magnets and poles that are like
How and why is the earth like a giant magnet?
How is electricity related to magnetism?
How is an electromagnet made?
How might you increased the power of an electromagnet?
View “How to Build a Simple Electric Motor” on YouTube. Sketch and label a diagram showing this design. What applications could this have?

3. Magnetism Magnetism is the properties and interactions of magnets
Magnets produce magnetic forces and have magnetic field lines called flux lines.

4. Magnetic Poles
Demo Flux lines
Magnets have two ends or poles, called north and south poles. At the poles of a magnet, the magnetic field lines are closer together.

5. The Laws of Magnetism
Demo
Unlike poles of magnets attract each other and like poles of magnets repel.

6. The earth is like a giant magnet!
The nickel iron core of the earth gives the earth a magnetic field much like a bar magnet.

7. Electricity and Magnetism How are they related?
When an electric current passes through a wire a magnetic field is formed.

8. What is an electromagnet?
Demo
When an electric current is passed through a coil of wire wrapped around a metal core, a very strong magnetic field is produced. This is called an electromagnet.