TCAP LESSON 19 ELECTRONMAGNETISM AND MANETIC FIELDS

VOCABULARY FOLDABLE I  Magnetic Force  Is a push or pull exerted by a magnet

Magnetic Field  The area surrounding a magnet in which the magnetic force exists

Electromagnetism  The production of a magnetic field by electric current

Electromagnet  A magnet that is made by passing an electric current through wire wrapped around an iron core

Electric Generator  Transforms magnetism into electrical energy

Electromagnetism and Magnetic Fields Notes page 5  A magnet is a material that exerts an attractive force on certain other materials.  Magnets are mode of iron, nickel, cobalt, or a combination of these elements with other materials.  Magnets exert a force on these metals and other magnets  Magnets can be used to produce electricity and electricity can be used to produce magnetism.

Magnet Force  A magnet has two poles: a north pole and a south pole. One pole cannot exist without the other  If you cut a magnet in half, both pieces will have north and south poles  Each pole exerts a magnetic force  Whether the force is a push or pull depends on what object the magnet is affecting and whether the poles are alike or different  Alike poles, repel, opposite poles, attract

Magnetic Field  The magnetic force of a magnet is strongest at the poles but it exists around the entire magnet  Earth’s magnetic field tends to trap particles coming in from the sun.  Without the magnetic field, these particles might be harmful to living things on Earth’s surface.

Electricity and Magnetism  When current flows through a coil of wire, the magnetic field produced around the wire is similar to that surrounding a bar magnet.

Producing Electricity  In a generator, a magnet is made to move inside a wire coil. The magnet may be moved by flowing water, wind or high-pressure steam.  This is how electric power plants work  The movement of the magnet produces an electric current in the coil

Electromagnetism and Magnetic Fields HW pg Which of the following could be used as the core of a simple electromagnet? a. pencilc. iron nail b. drinking strawd. aluminum foil 2. What will happen if the north poles of two magnets are moved toward each other a. The poles will attract each other b. The poles will repel each other c. Nothing will happen d. Electricity will be produced

HW 3. You have a coil of copper wire, a bar magnet, and an iron rod. What can you do with these items to produce an electrical current? a. Place the wire near the north pole of the bar magnet b. Move the bar magnet rapidly back and forth inside the wire coil c. Touch the ends of the wire to the poles of the magnet d. Bring the bar magnet near the end of the iron rod

HW 4. Which of the following materials is MOST LIKELY to be attracted to a magnet? a. A piece of metal b. A rubber ban c. A wooden match d. A cup of water

HW 5. What is the purpose of the iron core in an electromagnet? a. To hold the loops of wire in place b. To make the magnetic field stronger c. To make the field have north and south poles d. To change the direction of the magnetic field