This last semester we have been learning all types of things about Electricity and Magnetism. Lately we have been reviewing our last goals in our list of things that we will learn. I will list all of the last 13 goals. I hope that these goals and answers answer any questions that you have, and if any more questions feel free to leave a comment with a new question! ;)
- I can describe the properties and interactions of magnets.
The properties of magnets are iron, nickel, and cobalt , they are rare earth materials that we find in the earth. In a magnet you have these properties, and makes other magnets (rocks) with these properties become attracted to each other causing a magnetic pole and a magnetic field. Each magnet has a North Pole and a South pole. A magnetic field can be shown with sprinkles of iron over a paper, and under the paper you have a magnet. The following pictures show clearly the idea, one is a real life picture, and the other one is an animation.
This is an animation of a magnetic field
and shows the magnets poles.
This image shows how it shows with the iron sprinkles.
If you want to check out the websites where I got the majority of my information go tot he following links; http://en.wikipedia.org/wiki/Magnet
http://www.ndt-ed.org/EducationResources/HighSchool/Magnetism/magneticproperties.htm
2. I can describe how magnetic domains are arranged in a magnetic/ non-magnetic material.
A magnetic domain is the arraignment of how the atoms are alined in a rock. For example, each rock has atoms inside it, and each atom has electrons, causing a magnetic field around each atom. Now each magnetic field as its own direction. If all the atoms or the majority are alined, that will make or define the rack as a magnet, if the atomas are all pointing different directions, this mean that the rock isn't a magnet. Here are some pictures of magnetic domain, and a non-magnetic domain:
not a magnet a magnet
3. I can explain the connection between electricity and magnetism (electromagnetism).
Electricity and magnetism are connected for one reason. When you have a current caused by electricity, a magnetic field is made around the current because the movement of electrons in a wire. That is called electromagnetism. A great visual of electromagnetism:
For more information about electromagnetism vist: http://en.wikipedia.org/wiki/Electromagnetism
4. I can outline the difference between DC/AC current ans its uses.
A DC stands for a Direct Current. A Direct current has a commutator, while a AC that stand for an Alternating Current, wich has slip rings instead of a commutator, it also goes back and forth. Also a Direct Current has one flow for the electrons, not like an Alternating Current, where the flow of the current switches. For more information visit the following website, one that I recommend: http://www.ndt-ed.org/EducationResources/HighSchool/Electricity/directcurrent.htm
DC GENERATOR
5. I can explain why the Earth behaves like a magnet and the consequences of it.
The Earths magnetic field is crucial for life on earth. The Earths magnetic field acts as a shield that protects the Earth from certain radiation that comes from the sun and other stars. Also it protects the earth from getting other gases to come in. If those toxic gases get into our atmosphere it would create a flow of gases making our gases go to outer space, and the toxic ones will suffocate us, and we will not be able to breath without our gases(Carbon Dioxide and Oxygen).
6. I can explain the importance of grounding wires and using fuses/ circuit breakers.
Ground Wires are wires that are connected directly with the earth, getting some of the earths energy if needed. They act as a back up plan for neutral wires, and they also help to diminish the danger of getting electrocuted. Circuit breakers work as a tool to slow down the current in a circuit, so that it doesn't over heat up.
GROUND WIRE
BREAKS
7. I can explain how an electromagnet works and cite applications for them.
An electromagnets are made when there is a current then a magnetic field is made around the current. You use electromagnetism in motors, generators, and lifting heavy objects. Electromagnetism can be turned on and off by connecting or disconnecting the generator or motor from the battery (energy source).
8. I can explain how a simple motor works (parts and function).
In a simple motor you will have the following; Brushes, Armature, and a Commutator. Also a battery or a energy source. The Brushes touch the commutator from one end, and in the other end it touches the battery. They conduct the current to the armature, and they do not have any movement involved in this process. The Armature is in-between the permanent magnet. As the current is induced to the armature, around the armature a magnetic field is produced around it and so the North pole of the magnetic field is going to be alined with the north pole of the permanent magnet. The same thing is going to happen with the other side of the armature, the south pole of the armatures magnetic field will aline with the south pole of the permanent magnet. As north and north, and south and south will repel, the armature is going to start to move. When the armature almost spin completely, the gap in the commutator is going to allow it to spin 360 degrees, cause the process to start all over again, since its an alternating current.
9. I can describe how a generator and a transformer work.
A generator does the complete opposite from a motor, what a generator does is make the motion in a magnetic field to an electrical current. To do this you will need to induce a coil wire in a magnetic field, this sounds the same as a motor, although the difference is the parts it has. A Generator has; crank, brushes and slip rings, not like an motor that has a commutator and an armature instead. You can see this like in the picture below:
The generator uses the crank to turn instead of a battery, but it still needs the magnet for working. As the crank turns the armature has a current induced in it as it is in between the permanent magnet. The current goes through its path, then it turns when the armature has done a half turn, making this an AC circuit, for it is alternating. Also to keep in mind that the current is changing because it is going from South Pole to North Pole. The generator will then send the electricity to our homes, but the thing is that the electricity has to pass through a transformer first, since not all places have the same voltage, since it varies between 110v and 220v. The transformer will rearrange the voltage in the current to be suitable for its destinations voltage plug. The way that a transformer works is that first you must have an iron core, then there is a primary wire and a secondary wire each with a different role. The primary wire has the voltage that will be rearranged to go to your home, and the second wire has the "final product". To get the final product you have to see how you are going to set the transformer, if you want to increase the voltage then you will have more loops in the secondary wire, and if you want to diminish the voltage then you have to have less loops in the secondary wire, that all depends on the voltage in your plugs.
10. I can explain the importance of transformers to power grids.
When the voltage in the power leaves the power plant companies or location, you will find the voltage being very high. The voltage is very high so that it can travel long distances, till it reaches our homes, but then they pass through power grids and transformers so that the voltage is adapted to become adequate for our plugs. This is a very important step, if we didn't have this process, all of our appliances would burn, and we could have chances of being electrocuted.
This picture shows the process.
If you want to see more interesting information about poer grid distribution, you can check out the following website; http://science.howstuffworks.com/environmental/energy/power.htm
11. I can explain methods of power production and distribution .
There are two types of energies; Kinetic and Potencial Energy. Kinetic energy comes from motion, the greater the mass and speed of the moving object the more kinetic energy will be produced. Potencial energy is energy that comes from an object that has energy stored. Knowing these two terms then you can talk about 7 different types of energy.
- Fossil Fuels: conversion; from chemical energy to electrical energy. Some advantages from this source of energy are that it is very effective and it is easy to transport the energy form one place to another. Disadvantages; causes a lot of pollution, also the oil exploitation is very expensive, and limited as well.
- Biomass: conversion; you get the energy from burning anything that is organic, so it is potencial energy into electric energy. Advantages; enough Co2 is released to plant more trees, but not an excess of CO2. Disadvantages; the problem with this type of energy is that little energy is produced, and it isn't as efficient as other types of energy sources.
- Solar Energy: conversion; electromagnetic energy that comes from the suns light, becomes electrical energy. Advantages; the energy source is renewable, clean, no collateral damage, and it is ECO friendly. Disadvantages; it is very expensive, unattractive, and it doesn't work during the night or cloudy days making it impossible to control that fact that you WILL get energy.
- Nuclear Energy: conversion; nuclear energy to thermal energy to mechanical energy, to electrical energy. Advantages; this energy source doesn't increase global energy, and it also generats a lot of energy. Disadvantages; when an explosion there is a leak of toxic gases and radiation, also it impacts the environment, and it needs to be located near water, and it is hard to control from causing any damage or any mistakes.
- Hydroelectric Energy: conversion; hydroelectric to mechanical to electrical. Advantages; it is reliable, and you can control how much energy is produced. Disadvantages; need a lot of space to have the entire system built, it affects the people and environment around it because one side dries out a lot and the other one over flows.
- Wind Energy: conversion; from mechanical to electrical. Advantages; it is ECO friendly, the farms around them are still fertile to use as plantations, and it is clean as well as renewable. Disadvantages; it can only work in very specific places, it is quite loud and it becomes a threat for flying animals.
- Geothermal Energy: conversion; thermal to mechanical to electrical energy. Advantages; this source produces a lot of energy and it is efficient and it is ECO friendly. This energy only one disadvantage, the fact that it is very expensive.
12. I can describe the differences of 110v/220v and the main advantages.
13. I can describe the advantages and disadvantages of electrical energy.
Energy is just like the air, we don't notice id as much as we probably should. Electricity has so many advantages as well as disadvantages, what I think that it can help us, it helps us get around ad night, helps us use computers and learn more. The Disadvantages are that it pollutes, and we are harming the planet slowly, and now we really are seeing the results with Global Warming.
