For the past two weeks of classes we have been working on electricity.
We were told to build an electric motor, make an electromagnet, make a multiple choice quiz, etc.
Electric Motor
My electric motor was made of one battery, tape, a wire made of copper, a magnet, and a piece of cardboard.
I searched on youtube “how to build an electric motor” and also found some websites talking about them. I got a few ideas from every video I watched, and in the end, this is what I decided:
1. First I got a very small piece of cardboard, to put my project on top of.
2. Next, I got a copper wire and made it do an O shape with two ends that were sticking out.
3. Afterwards, I got two pieces of copper and made it into a shape that looked like the letter L but with a curvy side.
4. I got tape and glued the two pieces of wire to the battery.
5. I got a magnet and put it on top of my battery.
6. I put my project on top of the piece of cardboard.
7. I got the O shaped copper wire and put the two ends that were sticking out on the wires with an L on it.
Sorry if my explanation wasn’t very clear, so here is a picture and a video of my project so that you can understand it better:
This is my video:
And my image:
It wasn’t that hard to make it. My first one didn’t work actually, therefore I made a second one, which fortunately did. I learned that an electric motor can be used for lots of things for example cars, vacuum-cleaners, dishwashers, computer printers, fax machines, subway systems, sewage treatment plants, etc.
I observed that the copper would get really hot once I put it in its place, but it would cool down when I took it off or when I took off the magnet.
It works like this:
It works like this:
The electrons flow to the paper clips(in my case I used a wire) and then to the other copper wire and through the paths, until it got to the other side. While this happens, the magnetic field of the permanent magnet makes the coil move and making the wire spin. The electrons and the magnet got into perfect balance, so an insulator was needed and with it the current stopped, breaking the balance and completing the circle.
Electromagnets
As soon as we came back to school, we were assigned into groups and told to build an electromagnet. My assigned group was Felipe Santanna and Emyr Diniz. The materials we needed were simple: a nail, copper wire, a battery and some paper clips.
We had to wrap the copper wire around the nail and touch the ends of the wire to the battery. We had to wrap the wire around the nail very tightly so that our end results would be alright. Then, we had to try to pick up the paper clips and see if it stuck, and if it did it worked.
I observed that when the wire is connect to the negative and positive charges, the battery starts getting very hot and the nail becomes magnetic. I also observed that when my group and I disconnected the wires, the battery stopped getting hot and the nail stopped attracting the paper clips.
I learned that an electromagnet can be turned off and on. And the nail attracts the paper clips because of the flow of electrons. If it was not a complete circuit the electrons would not flow; the electrons created a magnetic field, which turned the nail into a magnet.
On the following week of school, Ms. Silva gave us twenty one questions, and told her that eight of those we had already learned and that we were going to review those eight topics. She separated us into groups; mine was the same one, Emyr and Felipe. She assigned each group a topic, and in the end we were all going to present it in front of the class. My assigned group was EM7. Here are the topics:
EM1: I can explain how electric charges interact.
EM2: I can give examples of how charges can be transferred between materials and explain them.
EM3: I can explain how an electric current is produced.
EM4: I can compare conductors with insulators.
EM5: I can explain how resistance affects current.
EM6: I can use Ohm’s law to calculate resistance, current and voltage.
EM7: I can build series and parallel circuits and describe its parts.
EM8: I can explain the relationship between power, voltage and current.
I understood some of the topics more than the others, but in the end I did understand all. Here is what I learned.
EM1:
Positive + negative charges attract each other;
Positive + positive charges repel;
Negative + negative charges repel each other;
Like charges a
All charges have invisible electric fields around them. It's an invisible region around an object that pulls or repels another charge.
The positive charges electric force is pulling outward, while the electric force of the negative charge is pulling inwards.
Positive + negative charges attract each other;
Positive + positive charges repel;
Negative + negative charges repel each other;
Like charges a
The positive charges electric force is pulling outward, while the electric force of the negative charge is pulling inwards.
EM2:
There are three ways of charges being transferred between materials: Friction(rubbing), conduction(direct contact) and induction(is caused by electric field of second object).
Friction-> electrons are transferred from one uncharged object to another one by rubbing.
Conduction-> electrons are transferred from a charged object to another one by direct contact.
Induction-> movement of electrons to one part of an object that is caused by the electric field of the second object.
There are three ways of charges being transferred between materials: Friction(rubbing), conduction(direct contact) and induction(is caused by electric field of second object).
Friction-> electrons are transferred from one uncharged object to another one by rubbing.
Conduction-> electrons are transferred from a charged object to another one by direct contact.
Induction-> movement of electrons to one part of an object that is caused by the electric field of the second object.
 |
| Person is rubbing hands; caused by friction |
 |
| Person is directly touching cell phone; caused by conduction |
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| Negative charges on fingers are being attracted to positive charges on doorknob while the negative charges are "moving away" from the negative charges on finger and the positive charges on finger are "moving away" from positive charges on doorknob; caused by induction |
Electric current is when the flow of electrons is a circuit and flowing continuously from one place to another.
An electric current can only be produced by voltage. A current is what creates an electric circuit(complete and unbroken path through which electric charges can flow). To produce electric current charges must flow continuously from one place to another. And current requires an electric circuit.
EM4:
Conductor is a material through which charges can flow easily because the electrons are loosely bound;
Examples of conductors- are silver, copper, aluminum, iron, etc.
Insulators is a material which charges cannot flow easily because the electrons are tightly bound; they are good to stop flow of charges. Some only slow down the current, while others(very few) stop the current.
Examples of insulators- are rubber, glass, sand, plastic, wood, etc.
Conductor is a material through which charges can flow easily because the electrons are loosely bound;
Examples of conductors- are silver, copper, aluminum, iron, etc.
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| Copper is a good conductor |
Insulators is a material which charges cannot flow easily because the electrons are tightly bound; they are good to stop flow of charges. Some only slow down the current, while others(very few) stop the current.
Examples of insulators- are rubber, glass, sand, plastic, wood, etc.
 |
| Sand is a good insulator |
EM5:
Firstly, one should know that when the resistance is high, the current is low; and when the current is high, resistance is low.
Four things that affect resistance are heat, length, material and width;
Heat- The electrical resistance of most materials increases as temperature increases and as the temperature of most materials decreases, so does resistance.
Length- The longer the wire, the more the resistance and the shorter the wire the less the resistance; Long wires have more resistance than short wires because less electrons flow through the long pipe than through the short one. The electrons in the long pipe slows it down because it bumps into more of the circuit's inner wall.
Width- The wire with small diameter has less electrons flowing through it than the wire with the large diameter because in the small one, there is less area through which the electrons can flow. Thin wires also have more resistance than thick wires.
Material- Insulators are tightly bound, making it hard for electrons to flow; Conductors are loosely bound, making it easier for electrons to flow; It depends on whether the material is an insulator or a conductor;
Firstly, one should know that when the resistance is high, the current is low; and when the current is high, resistance is low.
Four things that affect resistance are heat, length, material and width;
Heat- The electrical resistance of most materials increases as temperature increases and as the temperature of most materials decreases, so does resistance.
Length- The longer the wire, the more the resistance and the shorter the wire the less the resistance; Long wires have more resistance than short wires because less electrons flow through the long pipe than through the short one. The electrons in the long pipe slows it down because it bumps into more of the circuit's inner wall.
Width- The wire with small diameter has less electrons flowing through it than the wire with the large diameter because in the small one, there is less area through which the electrons can flow. Thin wires also have more resistance than thick wires.
Material- Insulators are tightly bound, making it hard for electrons to flow; Conductors are loosely bound, making it easier for electrons to flow; It depends on whether the material is an insulator or a conductor;
EM6:
Resistance= voltage/current.
Voltage(V)- the more energy electrons have, the stronger the voltage;
Current(I) or (A-amperes)- think of a waterfall: would represent how much water goes through the edge in a second;
Resistance(R) or (Ohms)- what stops material from flowing;
The voltage causes a current because the pressure from the voltage pushes the current;
Resistance= voltage/current.
Voltage(V)- the more energy electrons have, the stronger the voltage;
Current(I) or (A-amperes)- think of a waterfall: would represent how much water goes through the edge in a second;
Resistance(R) or (Ohms)- what stops material from flowing;
The voltage causes a current because the pressure from the voltage pushes the current;
EM7:
In a series circuit, the charges have only one path to take, while in a parallel circuit there are various different parts for charges to take.
Some differences in both are:
-The lightbulbs in the parallel circuit are always brighter than the ones in the series circuit because the electrons don't have to pass through all the lightbulbs/resistors.
-The resistance in the series circuit is greater than the ones in the parallel circuit since the electrons have to pass through all the lightbulbs and if one adds the resistance of all 3 lightbulbs it's greater than the resistance of only 1.
-In the parallel circuit the current is stronger because there are more paths for the current to flow through.
Battery-> energy source;
Lightbulb-> resistor;
Wire-> conductor;
In a series circuit, the charges have only one path to take, while in a parallel circuit there are various different parts for charges to take.
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| Series Circuit |
 |
| Parallel Circuit |
Some differences in both are:
-The lightbulbs in the parallel circuit are always brighter than the ones in the series circuit because the electrons don't have to pass through all the lightbulbs/resistors.
-The resistance in the series circuit is greater than the ones in the parallel circuit since the electrons have to pass through all the lightbulbs and if one adds the resistance of all 3 lightbulbs it's greater than the resistance of only 1.
-In the parallel circuit the current is stronger because there are more paths for the current to flow through.
Battery-> energy source;
Lightbulb-> resistor;
Wire-> conductor;
EM8: Power= voltage x current
I've explained what voltage and current are previously, however I haven't explain what is power:
Power(W-watts)- Rate at which energy is transformed from one form to another form.
Example: Hairdryers-> electrical energy to thermal energy to dry your hair
I've explained what voltage and current are previously, however I haven't explain what is power:
Power(W-watts)- Rate at which energy is transformed from one form to another form.
Example: Hairdryers-> electrical energy to thermal energy to dry your hair
Multiple Choice Electricity Quizzes
We were told to create a quiz about electricity with ten multiple choice questions(however no formulas, definitions or “all of the above” on our questions) and we had to put a link to it on our blog. Mine is on the post before this one J. Our teacher also told us to take a few of our classmates’ quizzes to prepare for hers. Ms. Silva was going to make one, using the questions we asked on our multiple choice quizzes.
After that we had more lessons on electromagnetism.
Bibliography of pictures:
http://www.google.com.br/imgres?um=1&hl=pt-BR&biw=1280&bih=629&tbm=isch&tbnid=1GH0XFcDFBtiJM:&imgrefurl=http://www.visualphotos.com/image/2x4812162/woman_rubbing_hands_together&docid=bHVbrrRMJ3Cl5M&imgurl=http://www.visualphotos.com/photo/2x4812162/Woman_rubbing_hands_together_33dlj0753rfs.jpg&w=431&h=670&ei=16GUT9ryJ4TY9ATy7tmqBA&zoom=1&iact=hc&vpx=267&vpy=219&dur=1814&hovh=280&hovw=180&tx=126&ty=178&sig=114836916919842941390&page=2&tbnh=131&tbnw=76&start=19&ndsp=28&ved=1t:429,r:1,s:19,i:112
http://www.google.com.br/imgres?um=1&hl=pt-BR&biw=1280&bih=629&tbm=isch&tbnid=4H9SRUdeFoDi5M:&imgrefurl=http://mybelojardim.com/nanotecnologia-criando-bateria-eternas/&docid=Cd5aScR0TyfZxM&imgurl=http://mybelojardim.com/wp-content/uploads/2011/06/touching-cell-phone3.jpg&w=400&h=337&ei=26KUT6yYK4W88ATv2Pz-Aw&zoom=1&iact=hc&vpx=760&vpy=180&dur=1429&hovh=206&hovw=245&tx=122&ty=98&sig=114836916919842941390&page=1&tbnh=125&tbnw=142&start=0&ndsp=25&ved=1t:429,r:6,s:0,i:78
http://www.google.com.br/imgres?um=1&hl=pt-BR&biw=1280&bih=629&tbm=isch&tbnid=6GFV6o0bmXyo7M:&imgrefurl=http://www.experienceproject.com/groups/Hate-Touching-Doorknobs/148073&docid=rw4YrkeB6LAZkM&imgurl=http://g.epcdn.net/ups/d17/kpsdtb2kj1.jpg&w=125&h=103&ei=FKOUT5WdAoGw8ASrqZ2LBA&zoom=1&iact=hc&vpx=847&vpy=76&dur=626&hovh=82&hovw=100&tx=93&ty=20&sig=114836916919842941390&page=2&tbnh=82&tbnw=100&start=19&ndsp=24&ved=1t:429,r:4,s:19,i:118
http://www.google.com.br/imgres?um=1&hl=pt-BR&biw=1280&bih=629&tbm=isch&tbnid=4JnDfmGZpFHnLM:&imgrefurl=http://gonzalolira.blogspot.com/2011/09/forget-goldwhat-matters-is-copper.html&docid=1GzNcYYLipsUjM&imgurl=https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhKE0YYNrkz7HfbwxDmH1NSknRIb0KRjj6yxD-kAysNVupMGpP11hfeQj6Hw04OWuVpJaRdqajsvcNyVZWFSsIqrOFO3ZkR4Deoqn04Vh4tVHCHJULYDA59mbtXx-7ZiQ9xQs3h2DC2nz4/s1600/0428_copper12.jpg&w=500&h=500&ei=JqWUT8rOMoOO8wSbjICBBA&zoom=1&iact=hc&vpx=120&vpy=293&dur=988&hovh=225&hovw=225&tx=145&ty=137&sig=114836916919842941390&page=1&tbnh=129&tbnw=145&start=0&ndsp=21&ved=1t:429,r:7,s:0,i:93
http://www.google.com.br/imgres?um=1&hl=pt-BR&biw=1280&bih=629&tbm=isch&tbnid=UtRVpi0fKCADTM:&imgrefurl=http://thevirtuosi.blogspot.com/2011/07/grains-of-sand.html&docid=NcMGqwf8mx-uiM&imgurl=https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjQk-xpbe2wq2oF_cl4bdTclsYFm3_wuYrwKVLAKnitc0h6cL8hqNK1U9awTPhhfhLX8Asu7PuZI8kcuFBk0yS_PMIOBuS9UhMSYVWJoYmzwqaoIxXkJkoGHfrM6ynzh377ZsBugwGeIpA/s1600/SandUDunesUSoft.jpg&w=1280&h=1024&ei=sqWUT9-HIYSm9AS7oaiNBA&zoom=1&iact=hc&vpx=290&vpy=181&dur=247&hovh=168&hovw=212&tx=70&ty=123&sig=114836916919842941390&page=1&tbnh=116&tbnw=150&start=0&ndsp=19&ved=1t:429,r:1,s:0,i:132
Bibliography of pictures:
http://www.google.com.br/imgres?um=1&hl=pt-BR&biw=1280&bih=629&tbm=isch&tbnid=1GH0XFcDFBtiJM:&imgrefurl=http://www.visualphotos.com/image/2x4812162/woman_rubbing_hands_together&docid=bHVbrrRMJ3Cl5M&imgurl=http://www.visualphotos.com/photo/2x4812162/Woman_rubbing_hands_together_33dlj0753rfs.jpg&w=431&h=670&ei=16GUT9ryJ4TY9ATy7tmqBA&zoom=1&iact=hc&vpx=267&vpy=219&dur=1814&hovh=280&hovw=180&tx=126&ty=178&sig=114836916919842941390&page=2&tbnh=131&tbnw=76&start=19&ndsp=28&ved=1t:429,r:1,s:19,i:112
http://www.google.com.br/imgres?um=1&hl=pt-BR&biw=1280&bih=629&tbm=isch&tbnid=4H9SRUdeFoDi5M:&imgrefurl=http://mybelojardim.com/nanotecnologia-criando-bateria-eternas/&docid=Cd5aScR0TyfZxM&imgurl=http://mybelojardim.com/wp-content/uploads/2011/06/touching-cell-phone3.jpg&w=400&h=337&ei=26KUT6yYK4W88ATv2Pz-Aw&zoom=1&iact=hc&vpx=760&vpy=180&dur=1429&hovh=206&hovw=245&tx=122&ty=98&sig=114836916919842941390&page=1&tbnh=125&tbnw=142&start=0&ndsp=25&ved=1t:429,r:6,s:0,i:78
http://www.google.com.br/imgres?um=1&hl=pt-BR&biw=1280&bih=629&tbm=isch&tbnid=6GFV6o0bmXyo7M:&imgrefurl=http://www.experienceproject.com/groups/Hate-Touching-Doorknobs/148073&docid=rw4YrkeB6LAZkM&imgurl=http://g.epcdn.net/ups/d17/kpsdtb2kj1.jpg&w=125&h=103&ei=FKOUT5WdAoGw8ASrqZ2LBA&zoom=1&iact=hc&vpx=847&vpy=76&dur=626&hovh=82&hovw=100&tx=93&ty=20&sig=114836916919842941390&page=2&tbnh=82&tbnw=100&start=19&ndsp=24&ved=1t:429,r:4,s:19,i:118
http://www.google.com.br/imgres?um=1&hl=pt-BR&biw=1280&bih=629&tbm=isch&tbnid=4JnDfmGZpFHnLM:&imgrefurl=http://gonzalolira.blogspot.com/2011/09/forget-goldwhat-matters-is-copper.html&docid=1GzNcYYLipsUjM&imgurl=https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEhKE0YYNrkz7HfbwxDmH1NSknRIb0KRjj6yxD-kAysNVupMGpP11hfeQj6Hw04OWuVpJaRdqajsvcNyVZWFSsIqrOFO3ZkR4Deoqn04Vh4tVHCHJULYDA59mbtXx-7ZiQ9xQs3h2DC2nz4/s1600/0428_copper12.jpg&w=500&h=500&ei=JqWUT8rOMoOO8wSbjICBBA&zoom=1&iact=hc&vpx=120&vpy=293&dur=988&hovh=225&hovw=225&tx=145&ty=137&sig=114836916919842941390&page=1&tbnh=129&tbnw=145&start=0&ndsp=21&ved=1t:429,r:7,s:0,i:93
http://www.google.com.br/imgres?um=1&hl=pt-BR&biw=1280&bih=629&tbm=isch&tbnid=UtRVpi0fKCADTM:&imgrefurl=http://thevirtuosi.blogspot.com/2011/07/grains-of-sand.html&docid=NcMGqwf8mx-uiM&imgurl=https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEjQk-xpbe2wq2oF_cl4bdTclsYFm3_wuYrwKVLAKnitc0h6cL8hqNK1U9awTPhhfhLX8Asu7PuZI8kcuFBk0yS_PMIOBuS9UhMSYVWJoYmzwqaoIxXkJkoGHfrM6ynzh377ZsBugwGeIpA/s1600/SandUDunesUSoft.jpg&w=1280&h=1024&ei=sqWUT9-HIYSm9AS7oaiNBA&zoom=1&iact=hc&vpx=290&vpy=181&dur=247&hovh=168&hovw=212&tx=70&ty=123&sig=114836916919842941390&page=1&tbnh=116&tbnw=150&start=0&ndsp=19&ved=1t:429,r:1,s:0,i:132
