Wind Turbine Generator Blog

Background-
      To understand how a wind turbine generator works, one must first understand the importance of the coils of wire and the magnets. After making the wire into a thick coil and aligning the four magnets on the shaft correctly, this creates a magnetic field which is what actually produces the voltage. Once the fan blades are powered by the fan blowing on it, the turbine will actually generate a voltage.

Materials-

      If someone where to recreate our turbine, they would need the following materials. PVC pipes for main unit of turbine, wood sheet for base, wood dowel for shaft, four magnets, copper wire, and a fan blade to attach to the shaft. We put the four magnets around the shaft, taking note of which direction they should be facing. We put the coil of wire above the magnets so that it would create a magnetic field between the two. We then put the fan blade on the end of the shaft so that it would catch the wind when the fan blew on it.

Results and Discussion/Tips-
     There were many different factors that led to the amount of voltage induced. First of all, friction is a big factor in how much voltage you will produce. If you want a higher voltage, try to make the friction as minimal as possible. However, you can also increase the voltage by having more coils or by making the one coil thicker. At first, our coil wasn't working so we had to make it thicker. This ended up helping significantly and allowed our turbine to actually produce a voltage. At first we tried making our own fan blades out of cardboard, but it ended up not working too great so I luckily found a small fan blade which we ended up using. My one most important piece of advice is to not procrastinate and actually get your turbine done. My group and I finished early so we were relaxing while other groups were rushing to finish their turbines. Good luck.

The Top Ten Most Interesting Topics of Physics

1. Electricity
While initially hard to fully understand, I found this topic the most interesting of the entire year. I really enjoyed talking about this because electronics are so common in our lives today, so actually learning about things applicable in my life was a blast. Learning about light bulbs and how houses were wired was very useful. I learned that you want your house to be wired in a parallel circuit so that if one appliance blows, the others will keep working, where they would all blow in a series circuit. I found this helpful as I now know why all the other appliances in my house keep working if a bulb blows.

2. Charges
I found the topic of charges surprisingly interesting. I really liked the big question that came along with this topic; why does our hair stand up after taking a sweater or hat off? I enjoyed how this was a relevant question in my life because I have had this happen before. I learned that the hat steals electrons from your hair as you take it off, and the like charges in your hair repel. Since your hair is light enough to stand up, it does when the charges repel.

3. Magnetism
This recent topic was another interesting one for me. I once again enjoyed the relevance of the material we were learning, and I have always found magnets interesting. While some of the specifics were not the most interesting, I liked learning about how credit cards work. I learned that the card has a magnetic strip with a code on the back with different levels of magnetism. When you swipe it, the card reader has coils that induces a voltage/current and detects the different levels of magnetism, ultimately sending this to a computer which translates the code. I found this very interesting and applicable.

4. Motors
I found motors to be interesting also because they are very relevant and useful in almost everyone's life. They are in cars, toys, and a countless number of other things. I learned that a motor is made up of two coils and magnets and they convert electrical energy to mechanical energy. It uses the coils and the magnets with an electric field to convert this energy. Actually making a motor was interesting as well, and I found this helpful yet engaging as I would encounter many motors later in my life.

5. Machines
Learning about machines was neat. I never realized how useful a simple machine like a ramp or pulley actually is until I learned about them. I learned that when using a ramp, the force is actually the same if you push a box up a ramp or just lift the box up. The difference is that the force is split up so that you don't have to exert all your force at once. This is what actually makes something like a ramp quite useful in our lives.

6. Newton's 1st Law
This was the very first topic we learned about in physics. Having never taken physics before this, it was very a very interesting topic to start off with. Newton's 1st Law states, "An object in motion will stay in motion, and an object at rest will stay at rest unless acted on by an outside force." It seemed simple enough, but when we talked about real world examples I actually understood it. I learned that the objects on a table will stay at rest when you pull the tablecloth out because of Newtons' first law.

7. Torque
Torque was confusing at first, but after learning more about it and it's applications, I had a much easier time understanding it. I even understood it well enough that Nolan, Walker, and I made a rap for our podcast about torque. I learned that torque=force x lever arm, and that this is helpful when talking about opening doors. Since the hinges of a door are far away, this creates a long lever arm and therefore requires only a small amount of force to exerted when opening the door. I found this interesting and helpful as I opened doors a lot, however I never thought of why the hinges were where they are.

8. The Earth's Magnetic Field
Similar to magnetism, but more specific in regards to earth's magnetic field. I really enjoyed learning about our planet's magnetic field because I learned several things I had not known before. The most interesting thing I learned was that the north and south of earth are the geometric directions, and not magnetic. The north pole is actually the magnetic south pole and the south pole is actually the magnetic north pole. This was a very interesting fact I learned from this topic. I will use this knowledge later in life by telling people and surprising (hopefully) them.

9. Magnetic Paper Clip
This is another sub-topic under magnetism, but I really enjoyed magnetism so I will keep writing more about it. I found the question of how a paper clip can be turned into a magnet interesting. I learned that the paper clip originally has unaligned domains, but when it is moved near a magnet, the paper clip's domains align. The paper clip now has a north and south pole, and when it is moved next to the magnet, it will attract because the poles will be opposite.

10. Work
No, not work on homework. Work is a topic we learned about along with power. Doing work on something means that you are exerting a force on it, and we generally connected this with carrying things. For example, the question "When you are holding/lifting a 10kg box and carrying it forward with you over 10m, how much work are you doing on the box?" This is a trick question, because you aren't actually doing any work on the box because of the fact that if the forces are parallel then no work is done. It was slightly confusing, but after I understood it, it was helpful and interesting.

Motor Blog

      The battery supplies voltage to the motor. From this voltage, it also allows current to run through the motor. The two paperclips on either end act as stands, however they must both be touching the ends of the battery so that current can flow through them. The magnet that sits on top of the battery creates the magnetic field that contributes to the wire actually spinning. The actual copper wire loop is the most important part. Once wrapped in a circular loop, it sits on top of the paperclip rests and will spin (assuming it works).
      We scraped the entire tail of one end of the copper loop and just the bottom half of the other tail. We did this because when the loop flips over, the current will be opposite from the force, so this was necessary in order to make it continue spinning.
      The motor actually turns for several different reasons. First, the magnetic field created by the magnet puts a force on the copper loop. Second, the current in the wire will flow where the wire is scraped, so the way in which we scraped the wire is important. Last, the direction of the force will change as the loop flips, so that is also why we scraped only the bottom half on one tail of the wire.

This motor could be used for several different purposes. Mainly, it could be used for education as a demonstration in school, such as we did. It shows that you can make a motor with simple household items. However, this could also be used to impress your friends, or to show off to your parents. Lastly, it could be used for simple entertainment. If you are easily entertained, you could have a blast watching the motor spin for hours and hours.

Unit 6 Blog Reflection

The first thing we learned about in this unit was charges and polarization. The first formula we learned was coulomb's law, which is used to find the force of a charge (F=k(q1q2/d2). Distance and force have a relationship where if the distance is doubled, the force will be 1/4. We learned the 3 different ways that an object can be charged; induction, friction, and contact. Induction is when a neutral object is charged by a negative object without actually touching (as seen in picture above). Friction is charging objects by rubbing them together, and contact and where a charged object transfers it's charge to another object. A big question we answered in this section was; why does a balloon stick to the wall after being rubbed on one's hair? Being one of the longer problems, I was worried at first but it doesn't seem as bad once you start learning the steps. We learned that the balloon steals the electrons from your hair by friction (makes it negatively charged), and then the wall polarizes as it gets closer to the wall. This means the protons move closer to the balloon than the electrons do. From coulomb's law, we can see that the force between the attractive force is greater than the attractive force, so the balloon sticks to the wall.

The next topic we learned about was electric fields. The formula corresponding to electric fields is E=f/q (Force of electric field). The lines in a electric field represent the strength of the field; the closer together they are they stronger they are. One question I had trouble with was; a positively charged particle is in an electric field and moves the left while increasing velocity. The question asks if the field is caused by a positive or a negative charge. This is tricky because it could be positive, negative, or both. The next thing we touched on was electric shielding. We learned that most electronics have a hard metal shell because it protects the interior from being broken by even one small charge that could come into contact with it. The shielding makes it so that there is no net charge on anything inside the box.

One of the main questions when learning about electric potential was; why is it that when a bird stands on one end of a power line it doesn't get harmed but it gets harmed when touching both ends? The answer to this question is quite simple. When the bird is only touching one end of the power line, the circuit is not complete, so no current will flow through the bird. However, when the bird touches both ends of the power line, the circuit is complete and current can flow through. Also, when the bird is touching both ends there is a potential difference and the bird will be harmed. Potential difference is just voltage, the difference between two currents. A capacitor is a device that stores current so that it can all be released in a short period of time, and then it must recharge. This is why a camera flash has to recharge after taking a picture. 

Ohm's law (V=IR) and electric potential difference were next. Ohm's law is voltage=current x resistance. I already went over potential difference a little bit, but it is just voltage. Voltage =joules/coloumb, also (change)PE/q.

The next things we learned about were types of current, source of electrons, and power. The two types of current are direct and alternating current. DC flows in one direction (ex- battery), and AC flows back and forth (ex- generator). We learned that the electrons are actually already in the lightbulb when it is turned on, or that the electrons are already in your body when you get shocked by an electric fence. The equation for this section is Power=(current)(voltage). This is used a lot in problems along with the previous equations.

Lastly, we learned about parallel and series circuits. Parallel circuits are wired in separate branches so that if one bulb goes out, the others don't. In a series, they are all wired together in one strand so if one goes out, they all go out. In a series, the resistance adds, voltage adds, and current stays the same. For parallel circuits, resistance will be cut in half, voltage will always be the same, and current adds. Are most homes wired in parallel or series? This was a common question we had, and the answer is parallel because if one bulb/appliance goes out, then the others will still work. A fuse is a device that limits the amount of current that can flow through at any given point. This prevents overloading of current because if it does overload, a wire in the fuse will melt and it will protect the appliances because it is wired in series. 

This was a very long and detailed unit. I had trouble remembering all of the specific formulas for each section, as well as the specific details about each thing we covered. However, I had fun actually learning all of these common things about electricity that I can now use to impress my family and other friends. I feel pretty well prepared for the test, after writing this blog post, as well as studying my notes and quizzes. I hope to ask more questions in class particularly for the quizzes we take.

Types of Current Resource

      This very well animated and pleasant video explains the difference between direct current and alternating current, as well as explaining some history of energy and also explains a better way to use this current.
      I found that this video helped me understand both ac and dc current, as well as the difference between them. It explained that ac current was more commonly used and was more efficient to supply certain machines, but dc current also has it's advantages.

Voltage resource

In this video, some guy explains current and voltage by giving examples and explaining in depth how they work. He also explains the measurements.

This video helped me grasp voltage because I learned that voltage is the difference in electric potential, and it is measured in volts. 

Final Mousetrap Car Blog

Our car (Zach and Nolan) went 5 meters in 4.28 seconds (3rd p
lace).

      At first, we used a very long frame made out of wood because we were initially going to use records for the rear wheels, but the records broke so we had to cut most of the frame off. We used a short, wooden frame because it is both light and sturdy, so that the trap does not have to use that much force in moving the car (mass determines resistance to acceleration). We used four CD's as our wheels because they were thinner and that meant less friction on the ground when it is rolling. Also the larger wheels will have a greater tangential velocity. We put balloons on the rear wheels for traction, because the balloons have more friction than the plastic CD's. We used wooden dowels for the axels because they were light and effective and connected to the wheels. We used another wooden dowel for the lever arm that attached to the trap, because it was sturdy and we could cut it if necessary. We also used gorilla glue throughout the whole car because it dries fast and is light.

      Newton's first law states that an object in motion stays in motion and an object at rest stays at rest unless acted on by an outside force. This relates to our car because our car would stay in motion unless acted on by friction or even the wall if it hits it. Newton's second law states that A=Fnet/m, or acceleration is inversely proportional to mass and directly proportional to force. This relates to our car because the heavier our car is, the slower it will accelerate. For example, we first had a lot of mass because of the big frame and it didn't accelerate, but after we shortened the frame and loss mass, it accelerated much faster.  Newton's third law states that every action has an equal and opposite reaction. This is relevant to our car because when the trap went off and the wheels pulled the car forward, the equal reaction was that the car pulled the wheels backward.

      The two types of friction present were kinetic and static. We didn't have any problems with friction in fact, but we actually used friction to our advantage by putting balloons on the two rear wheels. Since the balloon material has more friction than the plastic CD's, this allowed for more traction in the rear. We only put balloons on the back because they were actually the only power behind the car, as the front wheels just spun on the axel.
      We took into account friction when accounting for how many wheels we should use, but we figured that using four wheels would be more stable. We chose to use CD's for all four wheels, because they were thin and therefore would have less friction when rolling. However, since the CD's were bigger than some other wheels in the class, they had a slower rotational velocity because of the size. The other groups with small wheels had a higher rotational velocity because they only had to cover such a small distance. 

      The conservation of energy states that energy can neither be created nor destroyed. When relating this to KE and PE, we could say that the car has all PE just before it takes off, and then it has all KE at about the middle when it is moving the fastest. As it slows down and eventually stops, it then converts all of it's KE back into PE. We could also find the efficiency of our car by measuring the workout/workin x 100. 
      Our lever arm was approximately 2 feet. The length of the lever arm definitely had a impact on the car's performance. At first w
e had a very long lever arm, but it was so long that it couldn't generate enough power to accelerate. As a result, we shortened the lever arm so that the force was less when it had to pull the entire car. This is because we know that torque=force x lever arm. However, because of the shorter lever arm, the power output of our car was less because the torque was less on the car. 
      Rotational inertia/velocity both played a part in the wheels of our car. Since our wheels were bigger than some other small wheels, they had a lower rotational velocity. They also had a higher tangential velocity because a point on the wheel had to rotate more than a smaller wheel would have to. Having smaller wheels would allow a higher rotational velocity and would have probably been more helpful. 
      We can't calculate the amount of work the spring does on the car because both the force and the distance (work=force x distance) have to be parallel, and in this case they are perpendicular. We can't find the amount of PE that was stored in the spring and the amount of KE the car used because work=∆KE/∆PE. We can't calculate the force the spring exerted on the car because there are many other factors that are decreasing the force on the car, such as friction, mass, etc.
      Our final design was extremely different than our original design. Initially, we were going to have a long frame and have records as the rear wheels. However, after the records broke, we decided to use CD's for the rear wheels as well. We then were stuck with a very long frame that was quite heavy and four smaller wheels. This is what prompted the thought to change our design. After 2 failed test runs, we realized that it was much too heavy, so our last hope was to cut the frame out and glue the ends back together. This surprisingly worked, and the car accelerated and even made it the 5m after an adjustment to the string.
      Similarly to what I said previously, the only major problem we had was that our first design was too heavy and didn't accelerate at all. Our first minor solution ideas were to shorten the lever arm and to increase the width of the rear axel, but after it still didn't accelerate again, we knew we had to make a more major change. Near the end of class, we decided to cut the frame out and glue the sides back together to reduce mass. This actually worked very well and is what saved us in the end.
      If we were to do this project again, I would definitely consider making my car as light as possible, as well as using smaller wheels. Making the car small in general seemed to work the best, as the fastest car in the classes was quite small. Also making sure the axels are stable and secure so that there is minimal wobbling when the car is rolling.