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The Lemon Battery Experiment

Michael, Brijesh, Riccardo and I chose to do an interesting experiment about electrical charge, The Lemon Battery. Poking a zinc nail in one end of a lemon and a copper in in the other gave us our battery, free to be hooked up in circuit any way a battery could be.

Our Lemon Battery Experiment explored the way electricity powers things, specifically an LED. We made an array of lemons in such a way that near optimally produced enough watts to power a small LED. The main teaching point of the experiment was understanding the relationship between power (watts), voltage and current. The analogy we used to describe lighting the LED was that of a water tank. If the voltage is the pressure of the water tank, the current is the size of the hole that allows water or electricity to flow out, and produce power. Power = Voltage times current. We also showed that there are specific ways to wire your circuit if you want to increase either the voltage or current. Series circuiting, (positive to negative), will result in higher voltage while parallel circuiting (positive to positive, negative to negative), resulting in increased amperage. We ended up using 4 lemons in parallel hooked up in series with 3 other lemons. This gave us the amperage of four lemons, and the voltage of four lemons as well.

Another teaching point was where the voltage came from in our array of lemons. We talked about the difference in charge created when the citric acid in the lemons reacts with the zinc nail. The reaction causes the zinc atoms to lose electrons and that produces imbalanced charges and electrons flowing from the zinc to the copper. Hook it up in a circuit and it functions just as a battery!

Our results didn’t bring anything extraordinary, one lemon produced about .8 volts, and we were unable to get a measurement of the amperage of the system under different scenarios, too small of a measurement. Lighting the LED was an interesting challenge to try, having to figure out our way through the puzzles of electricity.

 

Lemon Experiment

In my group of Ryan, Brijesh, and Riccardo, we finally arrived at “The Lemon Battery Experiment” to use for our project. We discussed using different fruits and seeing what voltages each one yielded. Trying out Apples, lemons and potatoes, we found that all fruits [and vegetables] gave about one volt of electricity. In our initial experiments we were even able to light up a small LED bulb with some luck.

For our experiment  that we will bring to the High Schools, we were thinking about teaching the kids about circuitry and first, asking them to create a measurable voltage using wires and fruits. Then later we my challenge them to light the bulb if they had success with the first aspect of the experiment.

Electricity Generation Lab

In the most recent lab, we explored the ideas stated in Faraday’s Law. According to the law, chancing a magnetic field inside a coil of wire will generate a current through that wire. In the lab we used shake flashlights to simulate the idea. With a voltmeter attached to the coil inside the light, we were able to measure the voltage over time while shaking the apparatus. After averaging the data, we were able to make sense of i, and concluded that the more shakes we get in per minute, (more intense the shaking) the more current was generated in volts.

Shakes

Sum Squared of Volts

0

0.062

82

259.393

98

223.978

160

294.975

Lab graph generator

MIT Nuclear Reactor

The trip to visit the MIT nuclear reactor was one of the most exciting experiences I have had this year. The MIT reactor is only a 6 mW facility compared to ones legitimately used for electricity generation at 3000 mW.

 

The energy comes from the splitting of atoms if the element Uranium 235. Fission as a process is a chain reaction, where one neutron splits off from one atom, it whacks into another, causing another neutron to break off. This can be very dangerous if left unchecked, energy levels could overload and the akt could get too hot. Boron is used as a neutron capture element to prevent dangerous chain reaction that could cause the fuel to overheat. If the fuel does over heat, it cause the metal casing containing the fuel to become a catalyst and separate the hydrogen from the oxygen in the water around the fuel cell. This is a very dangerous thing that could cause an explosion to occur with that much heat and hydrogen in the containment room. Because of this reason all nuclear plants in the U.S. have a hydrogen valve somewhere in the containment room.

 

The experience walking inside the reactor and getting to see the inside of the containment room was slightly scary yet very exciting. After going through an airlock that keeps the inside pressure slightly lower we got to see the technology and means of research MIT students got to do with the reactor. And finally we had to pass two radiation tests to exit. The experience was incredibly exciting and certainly inspired me to want to work in the energy field in the future.

The trip to visit the MIT nuclear reactor was one of the most exciting experiences I have had this year. The MIT reactor is only a 6 mW facility compared to ones legitimately used for electricity generation at 3000 mW.

The energy comes from the splitting of atoms if the element Uranium 235. Fission as a process is a chain reaction, where one neutron splits off from one atom, it whacks into another, causing another neutron to break off. This can be very dangerous if left unchecked, energy levels could overload and the akt could get too hot. Boron is used as a neutron capture element to prevent dangerous chain reaction that could cause the fuel to overheat. If the fuel does over heat, it cause the metal casing containing the fuel to become a catalyst and separate the hydrogen from the oxygen in the water around the fuel cell. This is a very dangerous thing that could cause an explosion to occur with that much heat and hydrogen in the containment room. Because of this reason all nuclear plants in the U.S. have a hydrogen valve somewhere in the containment room.

The experience walking inside the reactor and getting to see the inside of the containment room was slightly scary yet very exciting. After going through an airlock that keeps the inside pressure slightly lower we got to see the technology and means of research MIT students got to do with the reactor. And finally we had to pass two radiation tests to exit. The experience was incredibly exciting and certainly inspired me to want to work in the energy field in the future.

Solar Panel Experiment

An interesting experiment that we did in class the other day was determining what affects the efficiency of solar panels. The variables we tested were distance the light was from the panel i.e. brightness, and the color of the light hitting the panel, simulated by placing translucent strips of plastics of different color in between the sensor and light source.

Solar blog 2Solar blog

The results showed that more volts were produced when the light was the brightest (closest to the sensor). Additionally, out of the 3 colors we tested (red green and purple), green light produced the highest voltage at .40 followed by purple at .35 then red at .32. Unfiltered light had the most with .47.

Tom Vales Presenation

When Tom Vales visited class the other day he brought a small Tesla coil he used to demonstrate an old idea of Tesla’s, wireless electricity. While running a current through the coil of wire, he demonstrated how the coil produces an electric field that he used to light a fluorescent light bulb. He continued to explain how such a phenomenon as wireless electricity would have worked back in Tesla’s time to provide light in everyone’s home. In that time, if everyone were to run a small Tesla coil in their house somewhere, say the basement for convenience, it could power their lights and give power to older appliances that didn’t use the complex and intricate circuits used by modern appliances that us circuit boards.

If we were to try to use Tesla coils for wireless electricity today there would be a huge drawback that makes this method not viable. The fragile and complex circuits used in most electronics, cell phones and computers for example, would be cooked by the high energy. Anyone who keeps a Tesla coil in their house to power the lights and maybe a refrigerator would not be able to own a computer of any kind or use phones, iPods, etc.

Another use of the Tesla coils that Vales eluded to was the popular trend of using Tesla coils to produce music. By changing the frequency the current oscillates or alternates, the pitch of the buzzing that the Tesla coils give off changes, and can be precisely controlled to make or replicate musical rhythms. A popular tactic when doing this is to use multiple coils since a single one cannot replicate harmony that may exist in a given song.

Tesla Coil Music, Secrets by One Republic

Pandora’s Promise

The movie Pandora’s Promise gave an interesting argument for nuclear energy, bringing the viewer on a journey from the Japanese Fukushima power plant, and the areas of Nagasaki and Hiroshima, even through the site of the Chernobyl nuclear accident and finally ends up analyzing the role of nuclear energy in the United States and the rest of the world.

I really like the path the movie took, first  starting out with the counter argument, looking at mos of the public concerns with nuclear energy and their association with nuclear weapons. Then the movie did a great job of arguing why these opinions are wrong and exposing the science that shows how good nuclear energy can be, and how inflated the negative effects are.

Towards the middle of the movie, the focus shifted to the importance of moving beyond coal and oil. It expressed the importance of clean energy for growing economies and countries. The movie looked to nuclear energy as the answer, where one pound of uranium creates as much energy as 5000 barrels of oil, with minimal waste and zero emissions from the process itself. The total waste of all nuclear energy could be contained in a nine foot high by 300 foot area. These convincing points were introduced as not only evidence for the movies argument but to counter the opposition’s argument, which made the movie that much more effective at arguing its point.

One aspect of their argument that continued throughout the whole movie wa the little yellow radiation measurer, that showed how natural radiation can even surpass the radiation left behind by the Chernobyl accident.

The most interesting part of the movie, and the one which i am most skeptical about, was where it claimed that the U.S. has bought Russian nuclear warheads and converted into fuel. If this is true, it is an amazing step and precedent to follow in terms of getting rid of nuclear weapons, and adopting nuclear power. I am skeptical however simply because it isn’t an idea i have heard of and is something that seems like I would know about if it was true. A healthy skepticism is good, but there is no reason to doubt it is true more than any other piece of the movies argument.

 

In class we performed an experiment to confirm both newtons second law of motion and the law of conservation of energy.  Our experiment involved using a motor, pulley and string to lift a varying amount of weight. Another variable we tested was changing the power level of the motor.

The data below was collected by the NXT hooked up to the motor or calculated using some of the data collected. The graphs, also below, confirm the two principles we learned in class. Law of Conservation of Energy- This was confirmed by the data in the Battery Discharge vs Potential Energy graph. As the amount of energy discharged from the battery in the system increased, the the potential energy of the mass increased. If we had an exact measurement and units for the amount of energy discharged from the battery, it would be very close to the amount of PE gained by the hanging mass, and would further the understanding of The Law of Conservation of Energy.

Newton’s Second Law of Motion was also confirmed in this lab. now looking at the graph titled Mass vs Acceleration we see that as the mass of the item being lifted increases, the amount of acceleration it experiences is less. Newton’s law states that force = mass * acceleration, so the decrease in acceleration would be proportionate to the increase in mass to keep the same product of the two.

Demand Response For Carbon Cutdowns

An unfortunate fact of Physics is that 100 percent efficiency cannot be achieved. It is simply the way thermodynamics work. The second law of thermodynamics explains that energy always wants to move to the point of entropic equilibrium, or that heat wants to move toward cooler areas versus hotter areas of space.

100 percent efficiency would certainly be wondrous to have for Demand Response.This procedure makes sure that the power companies accurately and precisely provide the public with an appropriate amount of electricity while not producing so much that it becomes too inefficient.

This is certainly not an easy task. Not only do we have to calculate the amount using multiple variables, but most of the variables are estimated based on past trends. One clear trend is that the warmer the temperature in the summer, the more electricity is used by people blasting the AC at home or work, and the same goes for heat in the bitter months of winter.  The goal should always be to estimate more accurately as to save waste electricity from being produced, especially in a time where cutting down on carbon emissions is becoming so important.

Some interesting ways companies have been trying to get people to use less energy is to actually pay them to be limited to a set amount of energy. This is a win, win situation as less energy is being used by the consumer who participates, and engineers have an easier time predicting the amount of energy used, at least for that specific household of business.

 

 

http://www.marketwatch.com/story/enernocs-demand-response-network-provides-relief-to-strained-electricity-grids-during-extreme-cold-weather-2014-01-08

http://www.allaboutscience.org/second-law-of-thermodynamics.htm

http://www.coned.com/energyefficiency/demand_response.asp

Sawyer Library

The Sawyer Library has some incredible resources available to help out with research. The Librarians themselves can help find any book you could want to use for a research paper. Probably the most useful resource the library can offer me comes with their online databases. Accessed from the school website, they can give informational articles about anything from science to political issues. The Librarian recommended to use the “Access Science” link  for various science research, and is a good place to start looking for information about demand response. The last thing the guide recommended was to check out the 9th floor of 73 Tremont. Up there is the Sawyer Library Commons, a quiet place to work that is a comfortable atmosphere, and not too crowded. These pieces of knowledge never would have come to me without the tour, so I am glad I got to partake in it, and look forward to using the resources available.