What is the difference between alternating and direct current.
Alternating flows back and forth, Direct flows in only one direction.
100
Explain the energy transfer in an electric motor.
Electrical energy to mechanical.
100
What is the purpose of a transformer?
To increase or decrease voltage
100
How are nonmagnetic, magnetic, and magnet materials different
Nonmagnetic does not have domains, Magnetic have domains but they are not lined up, and magnets have domains that are all lined up.
100
How do you make an electromagnet?
Coil of wire with a current around a magnetic material.
200
What is the main difference between an alternating current generator and a direct current generator?
A direct current generator has a commutator
200
What is an electric motor made up of?
Coils of wire around iron and magnets.
200
Explain why a compass works and how.
The Earth has a magnetic field. The needle is magnetized so it always points north.
200
What happens when a magnet is cut in half?
It creates two new magnets
200
How do you make an electromagnet stronger?
More coils or more voltage.
300
How can you use alternating current on things that need direct current?
An AC/DC converter.
300
What part of the electric motor keeps the electromagnets rotating?
Commutator.
300
What is created around a wire when electricity is flowing.
Magnetic Field
300
Which part of the magnet is the strongest and why?
The polls because that is were the most concentration of field lines are.
300
What are two benefits of an electromagnet that permanent magnets do not have?
You can turn them on and off. You can vary the power
400
Where is alternating and direct current found?
Alternating is made by power plants and is in the wall outlets, Direct is found in all batteries.
400
Compare and contrast an electric motor with a generator.
They both are physically the same they just work oppositely.
400
How is magnetism like electricity?
They can both make each other. They both have field of energy around them
400
What is the name of the natural magnet?
Lodestone
400
Explain how a transformer works. (not what it does)
Alternating current is passed through a wire wrapped around an iron ring creating an electromagnet that is rotating. This magnetic field is rotating around other wire creating electricity in that wire.
500
Why is it important to have alternating current for a transformer to work?
It switches the poles moving the magnetic field so that it creates electricity in the other wire.
500
Generators us what kind of energy to convert into electricity.
Kinetic
500
What are the two ways electricity can be created in a wire?
Wire moving around a magnetic field or a magnetic field moving around a copper wire.
500
How can you create and destroy a magnet? List 2 ways for each
Rub a magnetic material with a magnet in the same direction, Store next to a permanent magnet for a long time, magnetizer.
Heat it, drop it, store it incorrectly.
500
How is electromagnetism used to save information?
It arranges domains in a way that they can be read my the device.