Mr., I made a diagram for you, because i was too lazy to look for some good images that could explain the situaion in the internet
Monday, 15 October 2012
Thursday, 19 April 2012
Goals 9 to 21
Introduction
Helloooo dear readeeers!!!! Miss Silva gave us a new assignment to show that we know what we were talking about for aproximately two months. So our job is to explain the 12 goals that were on a yellow sheet, from 9 to 21 about magnetism and electricity. So here we gooo!!!EM9. I can describe the properties and interactions of magnets.The magnets interact between themselves through the magnetic fields.
The magnet, as you see, has a south and a north pole, represented as the letters S and N. The lines that has the arrows are the magnetic field lines. That’s how magnets interact: with the magnetic field lines. As you observe the image, you can see that the arrows are always pointing from N to S. Also, the distance of them lines represents the strength of the field. That’s because if you put two magnets far away from each other they’ll not move, unless you put them closer. Because from far away, the magnetic field hasn’t got power enough to pull themselves towards the magnet that they’re interacting with. 
As you see, the poles are again represented in N and S, but now, it’s showing the interaction of two different pieces of magnets and explaining why the different poles are attracted from each other. In top part of the image, there is the interaction between two different poles. Since the arrows of the magnetic field lines are always pointing from the N to S pole, the two magnets are going to be stick together by themselves. So what we can learn from this is that opposites attract.
EM10. I can describe how the magnetic domains are arranged in a magnetic/non-magnetic material.
To make a material be magnetic, we need to align its magnetic domains. Magnetic domains are a group of atoms that that have their magnetic field aligned. Very small, huh? That only works for a ferromagnetic material. Let's take a look at an example.
Here we see an unmagnetized piece of iron. It has the magnetic domains pointing to random directions before it was magnetized. But why do the domains have to be aligned to be magnetized? Because the directions that the arrows are pointing cancels each other. For example, the arrow pointing upwards and the other pointing downwards cancel themselves. Now when we look at the iron after magnetizing it, the arrows are pointing all at the same direction. Now the magnetic fields of the atoms are all aligned. The more domains are aligned, the stronger the magnet will be. So in this case, this piece of iron is a very very very strong magnet. EM11. I can explain the connection between electricity and magnetism (electromagnetism).There are many ways to temporalily magnetize a material, and one of them is magnetizing through electricity. When electrons pass through the material, it aligns its domains, magnetizing it. EM12. I can outline the difference between DC/AC current and its usesFirstly, do not forget that electricity is generated by the move of electrons through a material. Secondly, AC / DC is not that rock band that we're talking about. 
The AC current is a short term for alternating current, which means that the electrons are constantly changing the direnction of their movement. To make the electrons move in a wire without a voltage source, we can use a magnet to generate electricity. When a conductor passes through a magnetic field, the electrons inside it will try to align with it, generating electricity. There is a little simulation that you can use to understand it: http://debscience9th.blogspot.com.br/2012/04/ac-current-simulation.html
PS: When you click on it, it'll download a file, but it's not a virus!! It's the program that will help you
PS2: It's on the pickup coil section :)The DC current is a little bit more different than AC current. It is the shortening of direct current, which means that it hasn't got an alternating current. The electrons just pass through a material, without changing direction. Batteries are the best examples of a DC current.
EM13. I can explain why the Earth behaves like a magnet and the consequences of it.
We don't exactly know why the Earth behaves like a magnet. Actually, no one really knows why. We only know that the Earth also has magnetism. There are some theories that explain this mysterious origin.
One of them explains it through the rotation of the Earth. As you know, the Earth has got two big movements: rotation and translation. The speed of the rotation is of aproximatelly 67000 miles per hour. That makes the electrons flow inside the Earth. And because the Earth has a lot of metal both inside and outside of it, the flowing electrons in the center of Earth magnetizes it. We don't actually know what are the consequences, because Earth's magnetism always existed, so no one really knows what will happen when the magnetism is shut down. But an expected consequence is the use of the magnetic field lines to make the compass work to guide us in everywhere in Earth.
EM14. I can explain the importance of grounding wires and using fuses/circuit breakers.The grounding wires are very important to our safety. A circuit is electrically grounded when charges flow directly from the circuit into Earth in a short circuit. So one way to protect people from electric shock and other electrical danger is to provide an alternate path for electric current. EM15. I can explain how an electromagnet works and cite applications for them.
An electromagnet is temporary magnet, that was caused by electricity. As I said before, the electrons align the domains of a metal, magnetizing it. An example is a lifting magnet, used in scrapyards to lift havy metal pieces, like cars. EM16. I can explain how a simple motor works (parts and function). 
This is a simple motor. There's a coil, a battery, permanent magnet, and wires. As you see, there are electrons running through the circuit. But one thing you can't see is the ink painted in the contact zone with the coil and the pins, avoiding the contact between those two and cutting the circuit for a fast moment. It is also covering only half of it. iding contact between the coil and the bent pins. I thought that the ink didn't play an inportant role at the functionin of the motor, but well... it does. 
Recall that the electrons magnetizes a ferromagnetic object when pass through it. So what happens is that the coil acts like a magnet, and it will try to align itself with the magnetic field of the permanent maget, right under it. Now, it's the ink's turn to play the important part. While a coil is still turning, it'll still have electrons passing though it. But when the ink contacts the pin, current is cut off, and the coil becomes only a piece of ferromagnet. Because of that, the coil will "fall" and turn to the side that the ink is not present, turning the current on again. It'll rotate, and it'll again turn to the side where ink is present, cutting off the current. This will repeat infinitely, until the battery dies, or any part of the circuit is removed. EM17. I can describe how a generator and a transformer work A generator is a device that transforms mechanical energy into electrical energy. (quote from the book :D). It can work generating AC current or DC current. 
This is a generator working in AC current. The armature, which is this blue piece of wire that is being rotated, has the two magnets around it. Recall that when a wire moves through a magnet, electrons are induced. That's what's exactly happening here. The wire is turning aroudn the magnetic poles, and thus There's a link that will help you a lot to understand this. http://www.walterfendt.de/ph14e/generator_e.htm
EM18. I can explain the importance of transformers to power grids .
The transformers, as I said before, change the voltage, or the force the electrons are pushed. What you see in the left image is a little map of the power grid. A power grid is a system that distributes electricity to certain areas. The importance of transformers in the power grids are that they play the most important role in there. If you think the power grid as a body, transformers could be the heart, and electrons would be the blood cells. Well, they would not exactly be the heart, only the step-up transformers would do that. Anyways, the transformers, as I said before, modifies the voltage. If you didn't get it, think this way: if the blood pressure is low, blood cells won't reach more distant areas. If the voltage is low, the electrons that are in more distant areas will not move. And that was the step-up transformer's part, that are present in the transmission substation and the power substation. Now, the step-down transformers, that are present in the transformer drum, right next to the little house, unlike step-up ones, decreases the voltage. That's because the voltage of your house is 110V or 220V, and the voltage in the high voltage transmission lines can reach 345000V. EM19. I can explain methods of power production and distribution.
We don't exactly know why the Earth behaves like a magnet. Actually, no one really knows why. We only know that the Earth also has magnetism. There are some theories that explain this mysterious origin.
One of them explains it through the rotation of the Earth. As you know, the Earth has got two big movements: rotation and translation. The speed of the rotation is of aproximatelly 67000 miles per hour. That makes the electrons flow inside the Earth. And because the Earth has a lot of metal both inside and outside of it, the flowing electrons in the center of Earth magnetizes it. We don't actually know what are the consequences, because Earth's magnetism always existed, so no one really knows what will happen when the magnetism is shut down. But an expected consequence is the use of the magnetic field lines to make the compass work to guide us in everywhere in Earth. EM14. I can explain the importance of grounding wires and using fuses/circuit breakers.The grounding wires are very important to our safety. A circuit is electrically grounded when charges flow directly from the circuit into Earth in a short circuit. So one way to protect people from electric shock and other electrical danger is to provide an alternate path for electric current. EM15. I can explain how an electromagnet works and cite applications for them.
An electromagnet is temporary magnet, that was caused by electricity. As I said before, the electrons align the domains of a metal, magnetizing it. An example is a lifting magnet, used in scrapyards to lift havy metal pieces, like cars. EM16. I can explain how a simple motor works (parts and function). This is a simple motor. There's a coil, a battery, permanent magnet, and wires. As you see, there are electrons running through the circuit. But one thing you can't see is the ink painted in the contact zone with the coil and the pins, avoiding the contact between those two and cutting the circuit for a fast moment. It is also covering only half of it. iding contact between the coil and the bent pins. I thought that the ink didn't play an inportant role at the functionin of the motor, but well... it does. 
Recall that the electrons magnetizes a ferromagnetic object when pass through it. So what happens is that the coil acts like a magnet, and it will try to align itself with the magnetic field of the permanent maget, right under it. Now, it's the ink's turn to play the important part. While a coil is still turning, it'll still have electrons passing though it. But when the ink contacts the pin, current is cut off, and the coil becomes only a piece of ferromagnet. Because of that, the coil will "fall" and turn to the side that the ink is not present, turning the current on again. It'll rotate, and it'll again turn to the side where ink is present, cutting off the current. This will repeat infinitely, until the battery dies, or any part of the circuit is removed. EM17. I can describe how a generator and a transformer work A generator is a device that transforms mechanical energy into electrical energy. (quote from the book :D). It can work generating AC current or DC current. This is a generator working in AC current. The armature, which is this blue piece of wire that is being rotated, has the two magnets around it. Recall that when a wire moves through a magnet, electrons are induced. That's what's exactly happening here. The wire is turning aroudn the magnetic poles, and thus There's a link that will help you a lot to understand this. http://www.walterfendt.de/ph14e/generator_e.htm EM18. I can explain the importance of transformers to power grids .
The transformers, as I said before, change the voltage, or the force the electrons are pushed. What you see in the left image is a little map of the power grid. A power grid is a system that distributes electricity to certain areas. The importance of transformers in the power grids are that they play the most important role in there. If you think the power grid as a body, transformers could be the heart, and electrons would be the blood cells. Well, they would not exactly be the heart, only the step-up transformers would do that. Anyways, the transformers, as I said before, modifies the voltage. If you didn't get it, think this way: if the blood pressure is low, blood cells won't reach more distant areas. If the voltage is low, the electrons that are in more distant areas will not move. And that was the step-up transformer's part, that are present in the transmission substation and the power substation. Now, the step-down transformers, that are present in the transformer drum, right next to the little house, unlike step-up ones, decreases the voltage. That's because the voltage of your house is 110V or 220V, and the voltage in the high voltage transmission lines can reach 345000V. EM19. I can explain methods of power production and distribution. 
There are various methods to generate electricity. The methods can vary according to which are it is generated. For example, in Brazil, the hydroelectric method is the most used one in the whole country because of the abundance of water. And in South Korea, fossil fuel generators are the most widely used method. Many other methods are present around the whole world: nuclear, solar, wind power, biomass, geothermal, and other ones that I never heard about. The distribution can be on ground and underground. The underground one is the one that we don't see, because it's underground.
The underground ones are not so popular as the on ground ones, because it was invented much after the people started using the other method. Even though expensive to change from on ground to underground method, my opinion is that the under one is better, keeping out the annoying pigeons and the fail of electricity when raining heavily. Now, the on ground method, which you see everyday, is the most popular one, as I said before. It can make an area very dangerous to kids, where they're educated to not run kites where power poles are present, but millions of kids die each year due to their foolish thinking of "this is never going to happen with me. Kites can't be dangerous."
EM20. I can describe the differences of 110v/220v and main advantages and disadvantages of each.
The 110V's advantages can be a good point in only some of the countries, like Brazil, because the big majority of Brazilian products (like television, for example) is adapted to 110V, which is the "almost standard" Volts. Contrary to what many people think, it is not economic and not safer. It is not economic, because if you decrease the voltage, you'll have to increase the current, forcing yourself to use more conductor, which will cost more when setting up a power pole, for example. It is also not safer than the 220V's one, because there'll actually be more current than it.
The advantage of 220V is that we can use less conductor. If you increase the voltage, the current will decrease, not forcing you to buy more conductor. Also, the resistance of the used conductor will decrease, making it more efficient.
EM21. I can describe the advantages and disadvantages of electrical energy.
The advantages of electrical energy are infinite. We can stay up late in night, when our ancestors didn't, we can have infinite entertainment, chat with friends whenever we want, ride the elevator (I consider it one of the best inventions of humanity), make computer work (the best invention ever after the fire), etc. But the disadvantages are that it is so efficient in fueling new kinds of entertainment that we can't sleep earlier, it makes us use the elevator (which really compromises on our weight), deteriorates our health in some ways, it harms nature very much, and it kills millions of people each year because of their little awareness.
Concluding my work, I think that electricity was like the fire to the pre-historical human. It was very useful and sophisticated our lives very much, but also made us disacknowledge the environment because of our selfishness that harms and destroys millions of areas of green lands.
Sources:
Interaction between two poles:http://www.google.com.br/imgres?um=1&hl=pt-BR&sa=N&biw=1024&bih=505&tbm=isch&tbnid=VYm0MTwtmKdEMM:&imgrefurl=http://www.antenna-theory.com/definitions/hfield.php&docid=eidHbpSazWZltM&imgurl=http://www.antenna-theory.com/definitions/magneticDipole.jpg&w=398&h=296&ei=DlmHT-SNLOHc0QHb4oTZBw&zoom=1&iact=hc&vpx=467&vpy=17&dur=2369&hovh=194&hovw=260&tx=135&ty=97&sig=108479742769172282079&page=2&tbnh=145&tbnw=193&start=10&ndsp=15&ved=1t:429,r:7,s:10,i:118
Interaction between two different poles: http://www.google.com.br/imgres?um=1&hl=pt-BR&biw=1024&bih=677&tbm=isch&tbnid=rCMVDdr68IuSXM:&imgrefurl=http://ap.smu.ca/crc/index.php%3Foption%3Dcom_content%26view%3Darticle%26id%3D57:background%26catid%3D36:magneticfields%26Itemid%3D55&docid=EOu6gezzc2o08M&imgurl=http://ap.smu.ca/crc/images/stories/magnetic_interaction.jpg&w=600&h=500&ei=lAmHT6uPGYW5twfflo3fBw&zoom=1&iact=hc&vpx=320&vpy=160&dur=553&hovh=157&hovw=188&tx=127&ty=54&sig=100345281978020858908&page=1&tbnh=151&tbnw=181&start=0&ndsp=14&ved=1t:429,r:1,s:0,i:66
Mr. Bean if you know what i mean: http://www.google.com.br/imgres?um=1&hl=pt-BR&sa=N&biw=1024&bih=641&tbm=isch&tbnid=EflhNkjisgGLLM:&imgrefurl=http://knowyourmeme.com/memes/if-you-know-what-i-meanmr-bean-rage-face&docid=o0hWF_NyyMvP5M&imgurl=http://i2.kym-cdn.com/entries/icons/original/000/008/549/If%252520you%252520know%252520what%252520I%252520mean..png&w=420&h=317&ei=uguHT5WlGMS1twe3tIjyBw&zoom=1&iact=hc&vpx=97&vpy=147&dur=368&hovh=195&hovw=258&tx=125&ty=99&sig=100345281978020858908&page=1&tbnh=130&tbnw=172&start=0&ndsp=15&ved=1t:429,r:0,s:0,i:66
Magnetic domais: http://www.google.com/imgres?um=1&hl=pt-BR&sa=N&biw=1024&bih=641&tbm=isch&tbnid=OV9pJ1Xbht6CfM:&imgrefurl=http://www.magnet.fsu.edu/education/tutorials/magnetacademy/magnets/page2.html&docid=uMCaZpBfEK2jVM&imgurl=http://www.magnet.fsu.edu/education/tutorials/magnetacademy/magnets/images/magnets-domains.jpg&w=167&h=232&ei=ZlmIT9LnI4Km8ATj1eG_CQ&zoom=1&iact=hc&vpx=823&vpy=159&dur=1481&hovh=185&hovw=133&tx=128&ty=79&sig=106260554236818170122&page=1&tbnh=145&tbnw=102&start=0&ndsp=15&ved=1t:429,r:4,s:0,i:74
Batteries: http://www.google.com/imgres?um=1&hl=pt-BR&sa=N&biw=1366&bih=631&tbm=isch&tbnid=zT9fUrimoiyJ5M:&imgrefurl=http://earth911.com/recycling/hazardous/single-use-batteries/&docid=unkMPc1e-g2AFM&imgurl=http://earth911.com/wp-content/uploads/2008/09/single-use-batteries.jpg%253F84cd58&w=300&h=300&ei=TJyNT-7mMKHjiALb482aCA&zoom=1&iact=hc&vpx=481&vpy=278&dur=371&hovh=225&hovw=225&tx=150&ty=110&sig=117998593968358107234&page=1&tbnh=142&tbnw=123&start=0&ndsp=20&ved=1t:429,r:8,s:0,i:83
earth’s magnetism: http://www.google.com/imgres?um=1&hl=pt-BR&sa=N&biw=1366&bih=667&tbm=isch&tbnid=7TJLvSmkw81N5M:&imgrefurl=http://oceanexplorer.noaa.gov/explorations/05galapagos/logs/dec22/media/magfield_600.html&docid=UDuVXgA7w7YH6M&imgurl=http://oceanexplorer.noaa.gov/explorations/05galapagos/logs/dec22/media/magfield_600.gif&w=600&h=450&ei=fKSNT4DdEJPgggetnIT1DQ&zoom=1&iact=hc&vpx=965&vpy=314&dur=153&hovh=194&hovw=259&tx=99&ty=70&sig=117998593968358107234&page=1&tbnh=148&tbnw=196&start=0&ndsp=18&ved=1t:429,r:10,s:0,i:87
lifting magnet http://www.google.com/imgres?um=1&hl=pt-BR&biw=1366&bih=667&tbm=isch&tbnid=4StKClTMyW83gM:&imgrefurl=http://www.moleymagneticsinc.com/Scrap___Demo_Magnets.html&docid=KpvsyOkg-CnWWM&imgurl=http://www.moleymagneticsinc.com/images/scrap3.jpg&w=350&h=358&ei=wUWPT8vAFcXm0QG8w73PDw&zoom=1&iact=hc&vpx=546&vpy=177&dur=951&hovh=227&hovw=222&tx=127&ty=80&sig=117998593968358107234&page=1&tbnh=136&tbnw=138&start=0&ndsp=21&ved=1t:429,r:2,s:0,i:70
Simple motor http://www.google.com/imgres?um=1&hl=pt-BR&sa=N&biw=1366&bih=667&tbm=isch&tbnid=4-3WfQxEoiOa9M:&imgrefurl=http://www.miniscience.com/projects/magnet_motor_kit/index.html&docid=75QxnPBq4ZbO9M&imgurl=http://www.miniscience.com/projects/magnet_motor_kit/Magnet_Motor_LL.jpg&w=443&h=289&ei=aEePT6j1BoWC8QSj9ZyGBA&zoom=1&iact=hc&vpx=618&vpy=375&dur=2573&hovh=181&hovw=278&tx=161&ty=139&sig=117998593968358107234&page=1&tbnh=146&tbnw=225&start=0&ndsp=15&ved=1t:429,r:12,s:0,i:92
Electric generator
http://www.google.com/imgres?um=1&hl=pt-BR&biw=1366&bih=667&tbm=isch&tbnid=XidrWGbGLt58ZM:&imgrefurl=http://www.tutorvista.com/content/physics/physics-ii/electricity/electric-generator.php&docid=dF2bKj81scZghM&imgurl=http://images.tutorvista.com/content/electricity/dc-generator.jpeg&w=379&h=285&ei=Ds2QT-P3G4qltweIxtXjBA&zoom=1&iact=hc&vpx=905&vpy=155&dur=2342&hovh=195&hovw=259&tx=160&ty=28&sig=117998593968358107234&page=1&tbnh=141&tbnw=187&start=0&ndsp=18&ved=1t:429,r:4,s:0,i:72
transformer http://www.google.com/imgres?num=10&um=1&hl=pt-BR&biw=1366&bih=667&tbm=isch&tbnid=luCi8WB-Pbho1M:&imgrefurl=http://www.gcse.com/gcse_science_physics_past_paper_j03_2.htm&docid=QTXYc1o7jupMlM&imgurl=http://www.gcse.com/ocr/step_up_transformer.gif&w=456&h=263&ei=NEaUT_SjL8jItge2jf21Cw&zoom=1&iact=hc&vpx=166&vpy=322&dur=3214&hovh=170&hovw=296&tx=183&ty=92&sig=117998593968358107234&sqi=2&page=1&tbnh=108&tbnw=187&start=0&ndsp=18&ved=1t:429,r:6,s:0,i:77
power grids http://science.howstuffworks.com/environmental/energy/power.htm
you don’t say http://www.tumblr.com/tagged/you-don't-say?before=1333911534
Interaction between two poles:http://www.google.com.br/imgres?um=1&hl=pt-BR&sa=N&biw=1024&bih=505&tbm=isch&tbnid=VYm0MTwtmKdEMM:&imgrefurl=http://www.antenna-theory.com/definitions/hfield.php&docid=eidHbpSazWZltM&imgurl=http://www.antenna-theory.com/definitions/magneticDipole.jpg&w=398&h=296&ei=DlmHT-SNLOHc0QHb4oTZBw&zoom=1&iact=hc&vpx=467&vpy=17&dur=2369&hovh=194&hovw=260&tx=135&ty=97&sig=108479742769172282079&page=2&tbnh=145&tbnw=193&start=10&ndsp=15&ved=1t:429,r:7,s:10,i:118
Interaction between two different poles: http://www.google.com.br/imgres?um=1&hl=pt-BR&biw=1024&bih=677&tbm=isch&tbnid=rCMVDdr68IuSXM:&imgrefurl=http://ap.smu.ca/crc/index.php%3Foption%3Dcom_content%26view%3Darticle%26id%3D57:background%26catid%3D36:magneticfields%26Itemid%3D55&docid=EOu6gezzc2o08M&imgurl=http://ap.smu.ca/crc/images/stories/magnetic_interaction.jpg&w=600&h=500&ei=lAmHT6uPGYW5twfflo3fBw&zoom=1&iact=hc&vpx=320&vpy=160&dur=553&hovh=157&hovw=188&tx=127&ty=54&sig=100345281978020858908&page=1&tbnh=151&tbnw=181&start=0&ndsp=14&ved=1t:429,r:1,s:0,i:66
Mr. Bean if you know what i mean: http://www.google.com.br/imgres?um=1&hl=pt-BR&sa=N&biw=1024&bih=641&tbm=isch&tbnid=EflhNkjisgGLLM:&imgrefurl=http://knowyourmeme.com/memes/if-you-know-what-i-meanmr-bean-rage-face&docid=o0hWF_NyyMvP5M&imgurl=http://i2.kym-cdn.com/entries/icons/original/000/008/549/If%252520you%252520know%252520what%252520I%252520mean..png&w=420&h=317&ei=uguHT5WlGMS1twe3tIjyBw&zoom=1&iact=hc&vpx=97&vpy=147&dur=368&hovh=195&hovw=258&tx=125&ty=99&sig=100345281978020858908&page=1&tbnh=130&tbnw=172&start=0&ndsp=15&ved=1t:429,r:0,s:0,i:66
Magnetic domais: http://www.google.com/imgres?um=1&hl=pt-BR&sa=N&biw=1024&bih=641&tbm=isch&tbnid=OV9pJ1Xbht6CfM:&imgrefurl=http://www.magnet.fsu.edu/education/tutorials/magnetacademy/magnets/page2.html&docid=uMCaZpBfEK2jVM&imgurl=http://www.magnet.fsu.edu/education/tutorials/magnetacademy/magnets/images/magnets-domains.jpg&w=167&h=232&ei=ZlmIT9LnI4Km8ATj1eG_CQ&zoom=1&iact=hc&vpx=823&vpy=159&dur=1481&hovh=185&hovw=133&tx=128&ty=79&sig=106260554236818170122&page=1&tbnh=145&tbnw=102&start=0&ndsp=15&ved=1t:429,r:4,s:0,i:74
Batteries: http://www.google.com/imgres?um=1&hl=pt-BR&sa=N&biw=1366&bih=631&tbm=isch&tbnid=zT9fUrimoiyJ5M:&imgrefurl=http://earth911.com/recycling/hazardous/single-use-batteries/&docid=unkMPc1e-g2AFM&imgurl=http://earth911.com/wp-content/uploads/2008/09/single-use-batteries.jpg%253F84cd58&w=300&h=300&ei=TJyNT-7mMKHjiALb482aCA&zoom=1&iact=hc&vpx=481&vpy=278&dur=371&hovh=225&hovw=225&tx=150&ty=110&sig=117998593968358107234&page=1&tbnh=142&tbnw=123&start=0&ndsp=20&ved=1t:429,r:8,s:0,i:83
earth’s magnetism: http://www.google.com/imgres?um=1&hl=pt-BR&sa=N&biw=1366&bih=667&tbm=isch&tbnid=7TJLvSmkw81N5M:&imgrefurl=http://oceanexplorer.noaa.gov/explorations/05galapagos/logs/dec22/media/magfield_600.html&docid=UDuVXgA7w7YH6M&imgurl=http://oceanexplorer.noaa.gov/explorations/05galapagos/logs/dec22/media/magfield_600.gif&w=600&h=450&ei=fKSNT4DdEJPgggetnIT1DQ&zoom=1&iact=hc&vpx=965&vpy=314&dur=153&hovh=194&hovw=259&tx=99&ty=70&sig=117998593968358107234&page=1&tbnh=148&tbnw=196&start=0&ndsp=18&ved=1t:429,r:10,s:0,i:87
lifting magnet http://www.google.com/imgres?um=1&hl=pt-BR&biw=1366&bih=667&tbm=isch&tbnid=4StKClTMyW83gM:&imgrefurl=http://www.moleymagneticsinc.com/Scrap___Demo_Magnets.html&docid=KpvsyOkg-CnWWM&imgurl=http://www.moleymagneticsinc.com/images/scrap3.jpg&w=350&h=358&ei=wUWPT8vAFcXm0QG8w73PDw&zoom=1&iact=hc&vpx=546&vpy=177&dur=951&hovh=227&hovw=222&tx=127&ty=80&sig=117998593968358107234&page=1&tbnh=136&tbnw=138&start=0&ndsp=21&ved=1t:429,r:2,s:0,i:70
Simple motor http://www.google.com/imgres?um=1&hl=pt-BR&sa=N&biw=1366&bih=667&tbm=isch&tbnid=4-3WfQxEoiOa9M:&imgrefurl=http://www.miniscience.com/projects/magnet_motor_kit/index.html&docid=75QxnPBq4ZbO9M&imgurl=http://www.miniscience.com/projects/magnet_motor_kit/Magnet_Motor_LL.jpg&w=443&h=289&ei=aEePT6j1BoWC8QSj9ZyGBA&zoom=1&iact=hc&vpx=618&vpy=375&dur=2573&hovh=181&hovw=278&tx=161&ty=139&sig=117998593968358107234&page=1&tbnh=146&tbnw=225&start=0&ndsp=15&ved=1t:429,r:12,s:0,i:92
Electric generator
http://www.google.com/imgres?um=1&hl=pt-BR&biw=1366&bih=667&tbm=isch&tbnid=XidrWGbGLt58ZM:&imgrefurl=http://www.tutorvista.com/content/physics/physics-ii/electricity/electric-generator.php&docid=dF2bKj81scZghM&imgurl=http://images.tutorvista.com/content/electricity/dc-generator.jpeg&w=379&h=285&ei=Ds2QT-P3G4qltweIxtXjBA&zoom=1&iact=hc&vpx=905&vpy=155&dur=2342&hovh=195&hovw=259&tx=160&ty=28&sig=117998593968358107234&page=1&tbnh=141&tbnw=187&start=0&ndsp=18&ved=1t:429,r:4,s:0,i:72
transformer http://www.google.com/imgres?num=10&um=1&hl=pt-BR&biw=1366&bih=667&tbm=isch&tbnid=luCi8WB-Pbho1M:&imgrefurl=http://www.gcse.com/gcse_science_physics_past_paper_j03_2.htm&docid=QTXYc1o7jupMlM&imgurl=http://www.gcse.com/ocr/step_up_transformer.gif&w=456&h=263&ei=NEaUT_SjL8jItge2jf21Cw&zoom=1&iact=hc&vpx=166&vpy=322&dur=3214&hovh=170&hovw=296&tx=183&ty=92&sig=117998593968358107234&sqi=2&page=1&tbnh=108&tbnw=187&start=0&ndsp=18&ved=1t:429,r:6,s:0,i:77
power grids http://science.howstuffworks.com/environmental/energy/power.htm
you don’t say http://www.tumblr.com/tagged/you-don't-say?before=1333911534
Monday, 16 April 2012
Friday, 17 February 2012
Electricity and Magnetism
Helloooo people!! Came back to the blog in two months!!!
They have several paths for the current to take. There are a lot of different ways that electricity than flow. If one of the light bulbs burns, unlikely from the series circuit, the others will continue on working, because the electricity finds new ways to go to the other bulbs. Another contrary trait of the parallel circuit from the series one, is that even though more light bulbs are added, the light will stay the same, not going dimmer. To understand this better, think of you drinking orange juice in a straw. If there is only one straw, you'll be okay with that, but since you (hypothetically) loooove orange juice, you put one more straw in the cup and you'll be drinking twice as much as orange juice you were drinking before. Something similar happens with the parallel circuit, but not with orange juices, and with electric charges. So the more bulbs are added, the more resistance will decrease, elevating the current flowing in the circuit.
Bibliography
Me Gusta face - http://www.google.com.br/imgres?q=foot&um=1&hl=ko&sa=N&biw=1280&bih=663&tbm=isch&tbnid=7_tOEkEwIOfBPM:&imgrefurl=http://erwinadr.blogspot.com/2011/09/foot-problems.html&docid=RDn394phcVNJ_M&imgurl=https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh66B10VtiyDn_InjdZgI5kH3sBiOZhfwZMODUZwzCGq1gwR5gk-Pv-w3bG1aHzZmB70rkoqhI_VP9WnDzCclto-8rpYLtqBUZrSmjqELrDzaRTmSRnKyYrI_F7VdmL4xHWscroZgyZD7U/s1600/phototake_rm_photo_of_flat_foot.jpg&w=493&h=335&ei=Pcg-T5-tGab00gH4osy8Bw&zoom=1&iact=hc&vpx=344&vpy=314&dur=213&hovh=185&hovw=272&tx=180&ty=61&sig=115941791216781142149&page=1&tbnh=144&tbnw=192&start=0&ndsp=18&ved=0CF0QrQMwBw
Photo of foot - http://www.google.com.br/imgres?q=foot&um=1&hl=ko&sa=N&biw=1280&bih=663&tbm=isch&tbnid=7_tOEkEwIOfBPM:&imgrefurl=http://erwinadr.blogspot.com/2011/09/foot-problems.html&docid=RDn394phcVNJ_M&imgurl=https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh66B10VtiyDn_InjdZgI5kH3sBiOZhfwZMODUZwzCGq1gwR5gk-Pv-w3bG1aHzZmB70rkoqhI_VP9WnDzCclto-8rpYLtqBUZrSmjqELrDzaRTmSRnKyYrI_F7VdmL4xHWscroZgyZD7U/s1600/phototake_rm_photo_of_flat_foot.jpg&w=493&h=335&ei=Pcg-T5-tGab00gH4osy8Bw&zoom=1&iact=hc&vpx=344&vpy=314&dur=213&hovh=185&hovw=272&tx=180&ty=61&sig=115941791216781142149&page=1&tbnh=144&tbnw=192&start=0&ndsp=18&ved=0CF0QrQMwBw
Photo of a hand - http://www.google.com.br/imgres?q=hand&um=1&hl=ko&sa=N&biw=1280&bih=699&tbm=isch&tbnid=EKEEDSBGbC1ZxM:&imgrefurl=http://www.ucl.ac.uk/news/news-articles/1006/10061602&docid=AmdcRrhmTuepoM&imgurl=http://www.ucl.ac.uk/news/news-articles/1006/hand_pic.JPG&w=521&h=593&ei=-9M-T7yuEOHe0QHg0933Aw&zoom=1&iact=hc&vpx=802&vpy=313&dur=2381&hovh=240&hovw=210&tx=111&ty=173&sig=115941791216781142149&page=1&tbnh=146&tbnw=128&start=0&ndsp=21&ved=0CIwBEK0DMBI
Wire - http://www.google.com.br/imgres?q=wire&um=1&hl=ko&sa=N&biw=1280&bih=699&tbm=isch&tbnid=VEKhYga_YheQiM:&imgrefurl=http://www.wiringproducts.com/contents/en-us/d198.html&docid=9Y6ea8oDIvqCHM&imgurl=http://www.wiringproducts.com/contents/media/thhn_wire_1.jpg&w=339&h=377&ei=2N0-T7OEN4L40gHXvv3GBw&zoom=1&iact=hc&vpx=403&vpy=302&dur=4393&hovh=237&hovw=213&tx=140&ty=177&sig=115941791216781142149&page=1&tbnh=168&tbnw=161&start=0&ndsp=18&ved=0CF0QrQMwBw
Battery - http://www.google.com.br/imgres?q=battery&um=1&hl=ko&sa=N&biw=1280&bih=663&tbm=isch&tbnid=SDkMWjsTdLUKxM:&imgrefurl=http://androidspin.com/2011/07/25/app-betterbatterystats-helps-you-gain-bettery-battery-life/&docid=elLSG7gRBm4XNM&imgurl=http://androidspin.com/wp-content/uploads/2011/07/battery.jpg&w=400&h=300&ei=Qt4-T8rYDMOv0AHl6syvCA&zoom=1&iact=hc&vpx=183&vpy=155&dur=6269&hovh=194&hovw=259&tx=201&ty=112&sig=115941791216781142149&page=1&tbnh=145&tbnw=184&start=0&ndsp=18&ved=0CEAQrQMwAA
Lightbulb - http://www.google.com.br/imgres?q=little+light+bulb&um=1&hl=ko&sa=N&biw=1280&bih=699&tbm=isch&tbnid=UpmdjWa84XRJ3M:&imgrefurl=http://walyou.com/flat-light-bulb-design/&docid=j_tIC5XppzD0KM&imgurl=http://www.walyou.com/img/flat-light-bulb-design-1.jpg&w=420&h=432&ei=yd4-T6zxDeLs0gHp4OTVBw&zoom=1&iact=hc&vpx=387&vpy=325&dur=1059&hovh=228&hovw=221&tx=138&ty=175&sig=115941791216781142149&page=2&tbnh=154&tbnw=143&start=18&ndsp=23&ved=0CKYBEK0DMBM
Copper photo - http://www.google.com.br/imgres?q=copper&um=1&hl=ko&sa=N&biw=1280&bih=699&tbm=isch&tbnid=nHHY1bhfskdPvM:&imgrefurl=http://mercuryreliance.wordpress.com/2011/01/19/copper-stockpiles-sign-of-coming-depression/&docid=bufuHdCA072CxM&imgurl=http://mercuryreliance.files.wordpress.com/2011/01/copper_1.jpg&w=500&h=437&ei=luE-T_aoD4eM0QHfqIDoBw&zoom=1&iact=hc&vpx=364&vpy=149&dur=10972&hovh=210&hovw=240&tx=129&ty=125&sig=115941791216781142149&page=1&tbnh=150&tbnw=172&start=0&ndsp=17&ved=0CEQQrQMwAQ
Series circuits - http://images.yourdictionary.com/series-circuit
Parallel circuit - http://www.google.com.br/imgres?q=parallel+circuit&um=1&hl=ko&sa=N&biw=1280&bih=699&tbm=isch&tbnid=jHvaX54Oj0hGYM:&imgrefurl=http://www.berkeleypoint.com/learning/parallel_circuit.html&docid=FAvb7yusysAviM&imgurl=http://www.berkeleypoint.com/images/parallel.jpg&w=194&h=422&ei=MP0-T4e5Jo2y0AH5h5TFBw&zoom=1&iact=hc&vpx=177&vpy=143&dur=459&hovh=331&hovw=152&tx=79&ty=150&sig=115941791216781142149&page=2&tbnh=159&tbnw=73&start=15&ndsp=20&ved=0CJMBEK0DMA8
So this time, we the 9th
grade, have to explain what we learned 'till now. Well... basically it is about
magnetism and electricity. :D
We had a sheet with
learning goals ( a yellow one, to not be lost by us), and we had to expain the
first 8 ones. Theeere we goooo!!
Goal 1
I can explain how electric
charges interact
There are two types of
charges: negative and positive. If we put two magnets carged positive, they’ll
repel themselves, just like when a pair of negatively charged magnets do when
put near each other. But if we put a positive and a negative magnet together, they'll attract each other.
So:
- Positive + positive = repel
- Negative + negative = repel
- Positive + negative = attract
 |
| Interaction between different types of magnets |
Goal 2
I can give examples of how charges can be trasferred between materials and explain them.
- Charging by friction is the transfer of electrons from one uncharged object to another by rubbing. The object that loses electrons becomes positive, and the object that gains electrons becomes negative.
For example:
When you rub the carpet with
hairy socks, the electrons moves to your socks, and the protons go to the
carpet. So you charged the socks negative and a part of the carpet positive.
- Charging by conduction is the transfer of electrons from a charged object to another by direct contact. Derp's foot, that was uncharged, now has a negative charge, because the sock passed the electrons to the foot just by touching it.
- Charging by induction is the movement of electrons in a single object caused by the eletric field of the second object. This may be difficult to understand. You’re not actually charging the object. You’re just making the charges of the objects move through itself. For example, Derp's hand is negativelly charged because of the rubbing on the carpet that passed the electrons, which spread through the whole body. Let's suppose Derp needs to go somewhere and is going to twist the doorknob. In that moment, the negative charges of the hands attracts the positive charges that were randomly moving inside the doorknob. That's charging by induction. :)
Goal 3
I can explain how an electric current is produced
First, an electric current is the continuous flow of electric charges through a material. In other words, it is just electrons passing through a material.
To create an electric current, we need to have something that will give us electrons, a something to be used as a "street" to have the electrons passing through it, and something that will make the electrons move. A voltage source (for example a battery), a wire, and a resistor (for example a little light bulb). If we connect all of them together, we'll create an electric current.
Goal 4
I can compare conductors with insulators
Conductors transfers electric charge well. Their atoms contain electrons that are bound loosely that are able to move throughout the material. Some examples of conductors are metal and copper.
Insulators do not transfer charge well. Their atoms, unlike the conductors, contain electrons that are bound tightly together. Some examples of insulators are rubber, plastic, and wood.
Curiosity
Are we good conductors? Why?
Compared to other insulators, yes. Because even though we have skin, which is an excellent insulator, and a lot of non-ionic substances, such as lipids, water, carbohydrates, and proteins, there are a lot of ionic substances, like iron and sodium. The average resistance of a human is approximately 6 meg Ohms (the measurement of resistance), while copper is only a few Ohms (depending on the length). But when compared to ionic substances, we are not a really good conductor.
Goal 5
I can explain how resistance affects current.
Resistance is me measurement of how difficult it is for charges to flow through a material. The greater resistance, the less current is flowing.
So how do we determine resistance? There are four categories.
I can explain how an electric current is produced
First, an electric current is the continuous flow of electric charges through a material. In other words, it is just electrons passing through a material.
To create an electric current, we need to have something that will give us electrons, a something to be used as a "street" to have the electrons passing through it, and something that will make the electrons move. A voltage source (for example a battery), a wire, and a resistor (for example a little light bulb). If we connect all of them together, we'll create an electric current.
Goal 4
I can compare conductors with insulators
Conductors transfers electric charge well. Their atoms contain electrons that are bound loosely that are able to move throughout the material. Some examples of conductors are metal and copper.Curiosity
Are we good conductors? Why?
Compared to other insulators, yes. Because even though we have skin, which is an excellent insulator, and a lot of non-ionic substances, such as lipids, water, carbohydrates, and proteins, there are a lot of ionic substances, like iron and sodium. The average resistance of a human is approximately 6 meg Ohms (the measurement of resistance), while copper is only a few Ohms (depending on the length). But when compared to ionic substances, we are not a really good conductor.
Goal 5
I can explain how resistance affects current.
Resistance is me measurement of how difficult it is for charges to flow through a material. The greater resistance, the less current is flowing.
So how do we determine resistance? There are four categories.
- Material - the resistance highly depends on this one. Of what the wire is made is very important. For example, a copper wire has much less resistance than a plastic one.
- Length - long wires have more resistance than short wires, which means that long wires don't have current as much as a short wire. If electricity was water and the wire was a pipe, a short one would transport more water than the long one at the same time
- Diameter - wires with big diameter has less resistance than small diameter ones.
- Temperature - for most of the conductors, the greater temperature, there is less current flowing through them.
Goal 6
I can use Ohm's law to calculate resistance, current or voltage.
Georg Ohm was a scientist that lived in the 1800s. He discovered that even if he changed the voltage and the current, resistance was not changed. He also did the discovery the law named after his surname, the Ohm's Law. Ohm's Law stated that the resistance is equal to the voltage divided by the current.
 |
| Ohms, the unit of measurement of resistance |
Goal 7
I can build series and parallel circuits and describe its parts
First, we have to know what are circuits.
- Circuits have devices that are run by electrical energy.
- A circuit has a source of electrical energy.
- Electric circuits are connected by conducting wires.
 |
| This is how a simple circuit looks like |
- Wire - connects other components
- Energy source - gives electricity to keep the circuit working
- Resistor - the energy output
- Switch (optional) - control the work of the circuit
Series Circuits
There is only one path for the current to take. Or the current goes clock wise or counter-clockwise, there is no other way. Also, if one of the light bulbs goes out, others can't work, even though nothing is wrong with them, because the current can't take a different way to be flowing. Another disadvantage is that the the light of the bulbs goes dim if more light bulbs are added. This happens because the more light bulbs are added, the more resistance will increase, consequently decreasing the current in a series circuits.
Parallel Circuits
They have several paths for the current to take. There are a lot of different ways that electricity than flow. If one of the light bulbs burns, unlikely from the series circuit, the others will continue on working, because the electricity finds new ways to go to the other bulbs. Another contrary trait of the parallel circuit from the series one, is that even though more light bulbs are added, the light will stay the same, not going dimmer. To understand this better, think of you drinking orange juice in a straw. If there is only one straw, you'll be okay with that, but since you (hypothetically) loooove orange juice, you put one more straw in the cup and you'll be drinking twice as much as orange juice you were drinking before. Something similar happens with the parallel circuit, but not with orange juices, and with electric charges. So the more bulbs are added, the more resistance will decrease, elevating the current flowing in the circuit.
Goal 8
I can explain the relationship between power, voltage and current
Power is the rate at which energy is transformed from one form to another. For example, a hair dryer has 1200 watts, and a computer has 150.
So how do you calculate it? Simple.
POWER = VOLTAGE X CURRENT
Voltage is the force that pushed the current forward. So by knowing the voltage and the current, you can calculate how much power has an electric appliance you've got.Bibliography
Me Gusta face - http://www.google.com.br/imgres?q=foot&um=1&hl=ko&sa=N&biw=1280&bih=663&tbm=isch&tbnid=7_tOEkEwIOfBPM:&imgrefurl=http://erwinadr.blogspot.com/2011/09/foot-problems.html&docid=RDn394phcVNJ_M&imgurl=https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh66B10VtiyDn_InjdZgI5kH3sBiOZhfwZMODUZwzCGq1gwR5gk-Pv-w3bG1aHzZmB70rkoqhI_VP9WnDzCclto-8rpYLtqBUZrSmjqELrDzaRTmSRnKyYrI_F7VdmL4xHWscroZgyZD7U/s1600/phototake_rm_photo_of_flat_foot.jpg&w=493&h=335&ei=Pcg-T5-tGab00gH4osy8Bw&zoom=1&iact=hc&vpx=344&vpy=314&dur=213&hovh=185&hovw=272&tx=180&ty=61&sig=115941791216781142149&page=1&tbnh=144&tbnw=192&start=0&ndsp=18&ved=0CF0QrQMwBw
Photo of foot - http://www.google.com.br/imgres?q=foot&um=1&hl=ko&sa=N&biw=1280&bih=663&tbm=isch&tbnid=7_tOEkEwIOfBPM:&imgrefurl=http://erwinadr.blogspot.com/2011/09/foot-problems.html&docid=RDn394phcVNJ_M&imgurl=https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEh66B10VtiyDn_InjdZgI5kH3sBiOZhfwZMODUZwzCGq1gwR5gk-Pv-w3bG1aHzZmB70rkoqhI_VP9WnDzCclto-8rpYLtqBUZrSmjqELrDzaRTmSRnKyYrI_F7VdmL4xHWscroZgyZD7U/s1600/phototake_rm_photo_of_flat_foot.jpg&w=493&h=335&ei=Pcg-T5-tGab00gH4osy8Bw&zoom=1&iact=hc&vpx=344&vpy=314&dur=213&hovh=185&hovw=272&tx=180&ty=61&sig=115941791216781142149&page=1&tbnh=144&tbnw=192&start=0&ndsp=18&ved=0CF0QrQMwBw
Photo of a hand - http://www.google.com.br/imgres?q=hand&um=1&hl=ko&sa=N&biw=1280&bih=699&tbm=isch&tbnid=EKEEDSBGbC1ZxM:&imgrefurl=http://www.ucl.ac.uk/news/news-articles/1006/10061602&docid=AmdcRrhmTuepoM&imgurl=http://www.ucl.ac.uk/news/news-articles/1006/hand_pic.JPG&w=521&h=593&ei=-9M-T7yuEOHe0QHg0933Aw&zoom=1&iact=hc&vpx=802&vpy=313&dur=2381&hovh=240&hovw=210&tx=111&ty=173&sig=115941791216781142149&page=1&tbnh=146&tbnw=128&start=0&ndsp=21&ved=0CIwBEK0DMBI
Wire - http://www.google.com.br/imgres?q=wire&um=1&hl=ko&sa=N&biw=1280&bih=699&tbm=isch&tbnid=VEKhYga_YheQiM:&imgrefurl=http://www.wiringproducts.com/contents/en-us/d198.html&docid=9Y6ea8oDIvqCHM&imgurl=http://www.wiringproducts.com/contents/media/thhn_wire_1.jpg&w=339&h=377&ei=2N0-T7OEN4L40gHXvv3GBw&zoom=1&iact=hc&vpx=403&vpy=302&dur=4393&hovh=237&hovw=213&tx=140&ty=177&sig=115941791216781142149&page=1&tbnh=168&tbnw=161&start=0&ndsp=18&ved=0CF0QrQMwBw
Battery - http://www.google.com.br/imgres?q=battery&um=1&hl=ko&sa=N&biw=1280&bih=663&tbm=isch&tbnid=SDkMWjsTdLUKxM:&imgrefurl=http://androidspin.com/2011/07/25/app-betterbatterystats-helps-you-gain-bettery-battery-life/&docid=elLSG7gRBm4XNM&imgurl=http://androidspin.com/wp-content/uploads/2011/07/battery.jpg&w=400&h=300&ei=Qt4-T8rYDMOv0AHl6syvCA&zoom=1&iact=hc&vpx=183&vpy=155&dur=6269&hovh=194&hovw=259&tx=201&ty=112&sig=115941791216781142149&page=1&tbnh=145&tbnw=184&start=0&ndsp=18&ved=0CEAQrQMwAA
Lightbulb - http://www.google.com.br/imgres?q=little+light+bulb&um=1&hl=ko&sa=N&biw=1280&bih=699&tbm=isch&tbnid=UpmdjWa84XRJ3M:&imgrefurl=http://walyou.com/flat-light-bulb-design/&docid=j_tIC5XppzD0KM&imgurl=http://www.walyou.com/img/flat-light-bulb-design-1.jpg&w=420&h=432&ei=yd4-T6zxDeLs0gHp4OTVBw&zoom=1&iact=hc&vpx=387&vpy=325&dur=1059&hovh=228&hovw=221&tx=138&ty=175&sig=115941791216781142149&page=2&tbnh=154&tbnw=143&start=18&ndsp=23&ved=0CKYBEK0DMBM
Copper photo - http://www.google.com.br/imgres?q=copper&um=1&hl=ko&sa=N&biw=1280&bih=699&tbm=isch&tbnid=nHHY1bhfskdPvM:&imgrefurl=http://mercuryreliance.wordpress.com/2011/01/19/copper-stockpiles-sign-of-coming-depression/&docid=bufuHdCA072CxM&imgurl=http://mercuryreliance.files.wordpress.com/2011/01/copper_1.jpg&w=500&h=437&ei=luE-T_aoD4eM0QHfqIDoBw&zoom=1&iact=hc&vpx=364&vpy=149&dur=10972&hovh=210&hovw=240&tx=129&ty=125&sig=115941791216781142149&page=1&tbnh=150&tbnw=172&start=0&ndsp=17&ved=0CEQQrQMwAQ
Series circuits - http://images.yourdictionary.com/series-circuit
Parallel circuit - http://www.google.com.br/imgres?q=parallel+circuit&um=1&hl=ko&sa=N&biw=1280&bih=699&tbm=isch&tbnid=jHvaX54Oj0hGYM:&imgrefurl=http://www.berkeleypoint.com/learning/parallel_circuit.html&docid=FAvb7yusysAviM&imgurl=http://www.berkeleypoint.com/images/parallel.jpg&w=194&h=422&ei=MP0-T4e5Jo2y0AH5h5TFBw&zoom=1&iact=hc&vpx=177&vpy=143&dur=459&hovh=331&hovw=152&tx=79&ty=150&sig=115941791216781142149&page=2&tbnh=159&tbnw=73&start=15&ndsp=20&ved=0CJMBEK0DMA8
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