Electricity and Magnetism

Describe the magnetic poles: strength, type

There are two magnetic poles on a magnet: north and south. Their opposite ends attract, and the like ends repel. Their magnetic fields always go from north to south. The force is strongest at the poles.

32. If two objects have increased charges on them, what happens to the strength of the electrical force? What will happen to the magnitude of the force if the particles get closer together? What happens to magnetic force as magnets move apart from each other?

If they have increased charges the, electrical force will increase. The magnitude of the force is the particles get closer together will increase the opposite will happen when the magnets move apart from each other.

26. What type of particles are moving in an electric current? What determines the direction of the force on the wire?

Negatively charged electrons are moving in the wire, the magnet applies a force to the moving charges. The direction of the force on the wire depends on the direction of the current and the direction of the magnet's field.

3. What is the charge on an atom? Why (discuss the proton and electron count in relation to each other).

A charge on an atom depends on the number of protons and electrons. If there are more protons, it's becomes positive. If there are more electrons, it becomes negative.

4. How can a neutral atom become positively charged? How can it become negatively charged? What are charged atoms called?

When an atom gains one or more electrons, it becomes negatively charged. If an atom loses one or more electrons, it becomes positively charged. Electrically charged atoms are called ions.

33. If you look at iron filings around two un-marked magnets, how could you tell if the magnet poles were north to north or north to south? What would you expect to see in each case with the iron filings? Draw a picture of each scenario.

You could tell if the magnet poles were North to North or north to south by looking at how the filings are arranged. If the filings are going across from each other and filling Space in the middle of the magnets, it is north to south because their attracting. If the filings or repelling each other and there's is visible space between the magnets, they are south to south or north to north because they are repelling. *Drawing on notability*

28. List the steps on how to make an electromagnet.

1. An electric current in a wire produces a magnetic field around the wire. 2. An electric current in a wire coil produces a magnetic field with a north and south poles. 3. Placing an iron core within the coil greatly intensifies the magnetic field. This device is an electromagnet.

29. What factors affect the magnetic strength of an electromagnet? How can the strength be increased - state two ways.

A ferromagnetic core can greatly increases the strength of the coil's magnetic field. This makes the electromagnet's force stronger. As the number of loops in the coil increases, the magnetic field of the electromagnet becomes stronger.

14. Describe magnetic field lines: direction, where are they strongest and how can you tell, where are they weakest and how can you tell?

A magnet's magnetic field can be represented by lines, called magnetic field lines. Magnetic field lines have a direction. Lines are closest together at the magnet's poles is where the magnetic force is strongest. As the field lines become farther apart, the field and the force become weaker.

16. Describe Earth's magnetic field: Why does Earth have a magnetic field (what is causing it?) How does it benefit life on Earth?

A magnetic field surrounds Earth like a bar magnet. Earth has a magnetic field because of molten iron and nickel in its outer core. Earth has a North and South Pole. It benefits life because Earth's magnetic field protects Earth from charged particles from by the Sun. These particles can damage living organisms if they reach the surface of Earth. Earth's magnetic field deflects most of these particles.

24. How do magnetic fields and electric currents affect a compass needle? Why?

A magnetic field surrounds a magnet. A magnetic field also surrounds an electric current. This is why a compass needle moves when placed near a current-carrying wire. The needle moves because the magnetic field around the wire applies a force to the compass needle.

25. What produces the magnetic field around a current-carrying wire? What is a current-carrying wire? What happens to the magnetic field as the electric current increases?

A magnetic field surrounds all moving charged particles. In a current-carrying wire, a wire carrying the flow of electric charge, the magnetic fields of the flowing charges combine to produce a magnetic field around the wire. The field around the wire becomes stronger as the current in the wire increases, or as more electrons flow in the wire.

12. What happens to the strength of the magnetic force with distance.

A magnetic force becomes stronger as magnets move closer together and becomes weaker as the magnets move farther apart.

20. When does a magnetic material behave like a magnet? What has to happen to the magnetic fields of the atoms in the material for it to act as a magnet?

A magnetic material behaves like a magnet when domains line up. Both have atoms grouped into magnetic domains. For an object to be a magnet, its magnetic domains must align. When the domains align, their magnetic fields combine, forming a single magnetic field around the entire material. This causes the object to become a magnet.

19. What is a magnetic material? What is a ferromagnetic material? (Elements) ?

A magnetic material is any material that is strongly attracted to a magnet. Magnetic materials sometimes have ferromagnetic elements. They are elements including iron, nickel, and cobalt, that have an especially strong attraction to magnets.

How are electric motors used in everyday life?

A system of levers connected to an electric motor produces the back-and-forth motion of the windshield wipers. Electric motors make the power windows go up and down. A compact disk player uses an electric motor to spin a CD and move a small laser across the disk. And now, electric motors are replacing gasoline engines in many cars.

6. What is an electric field? Describe the type of force electrical fields can apply to other objects.

An electric field is the region surrounding a charged object. Electric fields can apply a force called an electric force onto another object even if it is not touching that other object.

27. What is an electromagnet? List 3 ways that an electromagnet is it different from a permanent magnet?

An electromagnet is a magnet created by wrapping a current-carrying wire around a ferromagnetic core. -The magnetic field around an electromagnet can be turned off by turning off the current. An electromagnet is not a magnet without the current. With the current on, it becomes a magnet. -The the strength of an electromagnet can be controlled. The strength of an electromagnet depends on the number of loops in the electromagnet's wire coil. Also, increasing the electric current in the coil strengthens the magnetic force. -The poles of an electromagnet can be reversed. Changing the direction of the current in the wire coil reverses an electromagnet's north and south magnetic poles.

30. Electric motors spin. What is making it spin? Discuss the role of the electromagnet, like and unlike poles.

An electromagnets poles can reverse, so when the unlike poles attract each other, the electromagnet begins to spin. When an electric current is supplied to the motor, the unlike poles of the permanent magnet and electromagnet attract each other, causing the motor to begin to turn.

21. Why are most objects/materials non-magnetic? Talk about the magnetic field of the atoms in most objects.

Atoms act like tiny magnets, but in most materials's magnetic fields, the atoms point in different directions.. As the fields around the atoms combine, they cancel each other. Thus, most types of matter are nonmagnetic materials and are not attracted to magnets.

22. What happens to the magnetic domains in a nail when it comes close to a magnet?

Both are magnetic materials and have atoms grouped into magnetic domains. However, for an object to be a magnet, its magnetic domains must align. When the domains align, their magnetic fields combine, forming a single magnetic field around the entire material. This causes the object to become a magnet.

17. Why is a compass needle attracted to magnetic fields? Does it always point to the poles? Explain why or why not.

Earth's magnetic field exerts a force on the needle. A compass needle will line up with the Earth's field lines. A compass needle does not point directly toward the poles of a magnet. Instead, the needle aligns with the field lines and points in the direction of the field lines. Earth's magnetic poles and geographic poles are not in the same spot, so you cannot find your way to the geographic poles with only a compass.

18. Contrast Earth's magnetic poles to Earth's geographic poles.

Earth's magnetic poles are always what the compass will want to point towards. The Geographic poles are not in the same spot, it is away from the magnetic and are at an angle.

9. Where is the strongest part of an electrical field?

It the most intense near the electric charges

1. List and describe the particles in an atom: name, location, charge

Protons, neutrons, and electrons make up an atom. Protons have a positive charge and are in the nucleus of the atom along with the nuclei, which have a neutral charge. Electrons have a negative charge and are are found moving around the atom.

5. How do objects become electrically charged? What causes an object to become negatively charged? What causes an object to become positively charged?

Objects can become electrically charged because some objects hold electrons more loosely than other objects. So electrons can move from one object to another. When this happens the positive charge and negative charge on the objects are unbalanced. It is negatively charged when some of the electrons transfer over to the object, and the same goes for a positively charged object.

2. Describe the interaction between charged particles: How do oppositely charged particles interact? How do like-charged particles interact? How do charged particles interact with neutral particles?

Oppositely charged particles interact by attracting each other. Like charged particles repel each other. A positively charged proton and a negatively charged electron attract each other. Two protons, or two electrons, repel, or push away from each other. Neutral and charged do not attract or repel with each other.

7. Describe how electrically charged objects interact: oppositely charged objects interact in what way? Similarly charged objects interact in what way?

Oppositely charged particles will interact attract each other. Similarly charged particles repel each other. A positively charged proton and a negatively charged electron attract each other. Two protons, or two electrons, repel, or push away from each other.

11. Describe the forces between magnetic poles: how do similar poles interact? How do opposite poles interact?

Similar poles, north north and south south interact by repelling each other. Opposite poles, north and south, attract each other.

23. Compare and contrast temporary and permanent magnets.

Temporary: A magnet that quickly loses its magnetic field after being removed from a magnetic field is a temporary magnet. e.g. The nail is a magnet only when it is close to the bar magnet. There, the magnetic field of the bar magnet is strong enough to cause the nail's magnetic domains to line up. When you move the nail away from the bar magnet, the poles of the domains in the nail return back to normal. The nail no longer is a magnet. Permanent: A magnet that remains a magnet after being removed from another magnetic field is a permanent magnet. In a permanent magnet, the magnetic domains remain lined up. Some magnetic materials can be made into permanent magnets by placing them in a very strong magnetic field. This causes the magnetic domains to align and stay aligned. The material then remains a magnet after it is removed from the field.

What is a magnetic field?

The area of magnetic force around a magnet. It is an invisible field around all magnets and it applies a force onto others magnets.

15. Describe the magnetic fields formed when opposite poles are near each other. Describe them when same poles are near each other.

The magnetic fields formed when opposite where near each other showed attractions between them, and the iron filings used to represent it showed the poles where attracted to each other. When The same poles are near each other, the filing show the poles want to repel each other. The filings repel from each other.

8. What two factors affect the strength of the electric force between objects? How does each factor affect the strength of the electric force? Does it increase it or decrease it?

the total amount of charge on both objects and the distance between the objects are the two factors that can affect the strength of an electric force between objects. The more charge, the more strength between the objects. More distance decreases the force, and less distance increases the strength.