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

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?

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

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.

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

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.

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

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.