What forces come from Magnets?

1. What forces come fromMagnets?

2. Vocabulary • Electromagnet – a magnet that is powered by electricity

3. Magnets • http://www.wbrschools.net/technology2/ctrailers/science2.htm • Magnetism comes from a special alignment of an atom’s electrons as found in iron and many other metals. • Electric currents also create magnetic fields • How was magnetism discovered? Through prehistoric people who found magnetic rocks called lodestones

4. Magnets and Magnetic Fields • Magnetism is a force created by the motion of electrons in atoms. • Moving electrons produce magnetic fields. When electrons are aligned in the same direction, the fields around them combine to create a strong magnet.

6. North Pole and South Pole • Because the atoms in a magnet are aligned in the same direction, they form two regions called poles; north and south. • All magnets have a north and south pole. • Opposites attract; like poles repel

7. Making Magnets • Magnet Activity • Changing Alignment: • Rubbing a magnet along an iron bar will create a temporary magnet. • Magnets can be weakened or demagnetized by dropping or heating them. • Using an electric current. Electrons moving through a wire create a magnetic field around the wire.

8. Auroras • Colored lights that appear in the northern and southern skies are known as auroras. • Auroras are caused by Earth’s magnetic field.

9. Auroras

10. Lesson Wrap-Up • Atoms have small magnetic fields. In magnets, these fields point in the same direction, one larger, stronger magnetic field. • Electrons moving through a wire create a magnetic field around the wire. • Examples of magnets and electromagnets include doorbells, bullet trains, and electric motors.