| A | B |
|---|
| magnetic force | a magnet exerts a force on another magnet, on iron or a similar metal, or on moving charges. |
| where is the magnetic force the strongest | at the magnetic pole |
| All magnets have | two magnetic poles |
| Magentic poles that are the same | repel one another |
| Magnetic poles that are opposite | attract one another |
| What surrounds a magnet | a magnetic field |
| Can a magnetic fields exert magnetic forces | yes, a magnetic field can exert magnetic forces. |
| A magnetic field, which is strongest near the manget's poles, | will either attract or repel another magnet that enters the field |
| magnetosphere | is the magnetic field around the earth |
| within an atom, what spins around the nucleus | electrons |
| a magnetic domain is a | region that has a very large number of atmos with aligned fields |
| a ferromagnetic material such as iron can | be magnetized because it contains magnetic domains |
| When a material is magnetized | most of its magnetc domains are aligned |
| Are electricity and magnetism related in some way | Yesm the current in electricity produced a magnetic field |
| electricity and magnetism are | different aspects of a single force know as electromagnetic force |
| Beside a magnet, what can create a magnetic field? | A moving electric charge. |
| A coil of current-carrying wire that produces a magnetic field is called | a solenoid |
| an electromagnet is a solenoid | with a ferromagnetic core |
| How is the magnetic field of an electromagnet controlled? | By changing the current in an electromagnet |
| electromagnetic devices such as galvanometers, electric motors and loudspeakers | change electrical energy into mechanical energy |
| what is a galvanometer | a device that uses a solenoid to measure small amounts of electric current |
| an electric motor is | a device that uses an electromagnet to turn on an axle |
| all of the electric energy that turns on lights, that moves trains, that powers factories | comes from two aspects of the electromagnetic force |
| an electric current produces a magnetic field | and a magnetic field can be used to produce an electric current |
| electromagnetic induction is the process of generating a current | by moving an electrical conductor relative to a magnetic field |
| How if voltage induced in a conductor | by a changing magnetic field, this is called Faraday's law |
| a generator is a device | that converts mechanical energy into electrical energy by rotating a coil of wire in a magnetic field |
| The two types of generators are | AC generators and DC generators |
| Most powerplants today use | AC generators |
| a motor converts electrical energy | into mechancial energy |
| a generator converts mechanical energy | into electrical energy |
| A DC generator produces a | Direct Current |
| An AC generator produces an | Alternating Current |
| The electrical energy produced by power plants is | transmitted in very high volatages. These voltages are too high to be safely used in homes. |
| A transformer is a device | that increases or decreases the voltage and the current of two linked AC circuits. |
| A transformer changes voltage or current | by inducing a changing magnetic field in one coil. This changing field then induces an alternating current in a nearby coild with a different number of turns. |
| A step-down transformer | decreases voltage and increases current |
| A set-up transformers | increases voltage and decreases current |
| Most of the electric energy in the US is produced using | coal, other sources include water (hydroelectric), nuclear, energy, wind, natural gas, and petroleum. |
