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8/24/2007
Find an web article from a reputable news website that contains information about any type of projectile. The article must relate to some science topic this could include something having to do with the projectile of bullets or weapons but should not focus on killing!Write a short (1 paragraph) summary of the article and then describe how anything you have learned in the past week about projectile motion might relate to it (second short paragraph). Finish with a citation to the web article. Enter all of this under "Entry" below.

//Entry:// An article was read about paintball. A paintball is a small ball filled with paint that is shot out of a gun at 280-feet per second. The object of the game is to shoot as many people as possible with the paintballs. Some paintball fields are elaborately designed complete with makeshift amphibious vehicles, clouds of smoke, tanks, bunkers, trenches, and shoulder-fired rocket devices that shoot larger paintballs all on a 14 acre playing field with 4,700 players. Fired at close-range, a hit from a paintball can hurt quite badly. The equipment is usually quite expensive especially if it is high-quality and high-performance. Paintball is a high excitement game loved by many for the adrenaline rush it gives them. Many rules of projectile motion are included in paintball. The angle of the gun when the paintball is shot will affect the paintball’s distance and parabola. The velocity at which the paintball is shot will also affect the distance. The force of wind will affect the paintball’s trajectory as well. Last, gravity will affect the paintball just as it affects everything. A paintball, when shot, develops a parabola which is affected by the angle at which it was shot. A paintball flying through the air can be broken down into two components: a horizontal component, velocity forward, and a vertical component, gravity. The last rule of projectile motion that applies to a paintball is that if shot at the same time, two paintballs will hit the ground at the same moment. This proves that projectile motion does apply to paintball.

Koonz, Brian. "Adrenaline has millions rushing to play paintball." __NewsTimesLIVE__. 24/08/2007. NewsTimesLIVE. 26 Aug 2007 http://www.newstimeslive.com/news/story.php?id=1186569725&source=tabbox.

//Comment 1:// The entry was very good overall. The description of the article was clear and informative as was the paragraph connecting the article to what had been learned in science class. However, there were some important details about the article that seemed to have been looked over. Nearly a fourth of the article related to the fact there were paintball ranges at various military bases that helped in the training of U.S. soldiers. The article also mentioned that many of the paintball enthuasists that had been interviewed were soldiers who had been deployed in Iraq. Alexandre could have added some more information about the interviews, because they helped support the article and its title. The entry also seemed to be a list of facts that did not flow very well, however it was still good at informing the reader what the article was about. Other than those minor adjustments, Alexandre followed all the other style and content directions. He wrote in 3rd person, he had 2 paragraphs, he used age suitable words, and his explaination and summary were well written. In a nutshell, it was a job well done! Comments by- Rachel E.

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9/24/2007
Reflect upon the mystery density cube experiment. You may write in first person. Create a long paragraph addressing these questions:

1.) Was the scientific method necessary in this experiment? If not, why? If so, why? 2.) What made this experiment difficult? or was it easy? 3.) Is density very important in finding the identity of an unknown substance?

//Entry:// I have a few reflections on the Mystery Cube Density Experiment, or the MCDE. As in all experiments, the scientific method was necessary in the MCDE. Observations were first made on each cube to hypothesize what each cube was made of using a list of possible substances. Qualitative and quantitative observations were then made on each cube for a more complete knowledge of what the cubes were and for future reference. Research on each possible substance in the list was then conducted. The number one thing to research for was the density of each substance. After comparing densities between the researched densities of each material and the densities of the cube, a final decision was made on what each cube was made of. The knowledge of what each cube is made of was then shared in class so that the mystery was no longer a mystery. I wouldn’t say the experiment was hard to conduct, just very time consuming. It was simple, hypothesize what each cube is made of, get quantitative and qualitative data, research the substances, and make a final decision of what each cube is made of. The problem is that there were ten cubes and twenty different possible substances, this made the gathering of quantitative and qualitative data and the research of each substance take a long time. After this experiment, it is obvious that density is critical in the finding of what type of material something is made if. Since the density of an object does not change no matter what, an unidentified object that has the same exact density of a certain substance has a 99% chance of being made of that substance. There is 1% missing because there is the possibility that two substances have the same density, however unlikely that may be.

//Comment 1: Great Job Alexandre. Your paragraph followed the guidleines, and had a thourough analysis of the experiment. There were certain areas of the paragraph that could have used some improvement. When answering the second question involving the difficulty of the experiment, you branched aaway from the topic and talked about the scientific method. This made the paragraph sound slightly scattered. The ending sentence(s) also had a few things that seemed a little off, my assumption is that the 99% and 1% are made up statistics. So next time, you might want to use words like several, most, very little, slim, or other descriptive words instead of made-up statistics. I also think it would have been helpful to mention qualitative data and its importance in research. Overall, it was thorough and insiteful. Super Work Alexandre! ☺ -Rachel//

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10/16/2007
What is a flame test in your own words? How does this relate to the use of chemicals in fireworks? Make sure to include your MLA citations you may not use Wikipedia! . Entry: A flame test is used to find out what a certain substance might be. The type of element or compound something might be can be determined by doing a flame test and looking at what color the certain element or compound turns into when held in the flame of a Bunsen burner. Certain colors equal certain elements or compounds. To conduct a flame test, a wire loop must be cleaned by dipping it into hydrochloric or nitric acid, and then holding the loop in the flame of a Bunsen burner. If the loop doesn’t turn a different color, the loop is clean. If the loop does turn a different color, the cleaning process should be repeated. After the loop is cleaned, the tip of it should be dipped into the element or compound that needs to be tested and hold the tip of the loop covered in the substance right in the flame of the Bunsen burner. The color the substance turns into must then be observed. While making fireworks, flame tests can become very useful. If a firework that turns green when it explodes must be made, a flame test can be used to determine which chemical turns green when burned. Since exploding and burning is almost the same thing, it is certain that a chemical that turns a certain color when burned will turn the same color when exploded in a firework.

"Qualitative Analysis - Flame Tests." __About.com__. The New York Times Company. 16 Oct 2007 <[|http://chemistry.about.com/library/weekly/aa110401a.htm>.]

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11/1/2007
Go to this site: [|http://www.visionlearning.com/library/module_viewer.php?mid=55 .]Click on "Watch the Reaction with Sodium and Chlorine" In your own words and in third person, create a blog entry describing the reaction and explaining what is happening in terms of the bonding. Write a long paragraph. Explain in detail.

//Entry:// When combined, sodium and chlorine react violently to form Sodium-Chloride, or plain table salt. When sodium is dropped into a recipient holding chlorine, an ionic reaction occurs. Each sodium atom loses an electron to each chlorine atom. Sodium atoms become cations, positively charged atoms, and chlorine atoms become anions, negatively charged atoms. This transfer of electrons creates big amounts of energy so a violent reaction occurs. After the transfer, the two substances change into NaCl, a new substance made out of the combination of chlorine and sodium. This indicates that a chemical reaction occurred, not a physical reaction. The last substance is commonly known as table salt.

//Comment 1:// Alexandre did a good job on this blog entry. He was very, very thorough in his explanation. He explained in very great details whats really happening. He did a great job explaining the bond and the chemical reaction. His grammar is pretty good. There were a few comma and spacing errors, but other than that grammar was fine. All of his information is correct. I would give this an A. Good job!

-Megan H.

Comment 2: You did a good job with the long paragraph. You explained the bond thoroughly. There were a few grammatical errors and the last sentence was not clear. The information was correct though. Overall, it was a well written paragraph and if I were to give you a grade it would be an A.

Adam L.

REVISED BLOG ENTRY:

When combined, sodium and chlorine react violently to form Sodium-Chloride, or plain table salt. When sodium is dropped into a recipient holding chlorine, an ionic reaction occurs. This is because it’s a bond between a metal and non-metal. Bonds between metals and non-metals are always ionic. In this case, sodium is the metal and chlorine is the non-metal. Sodium needs to lose and electron to look like neon, and chlorine needs to gain an electron to look like argon. So each sodium atom loses an electron to each chlorine atom. Sodium atoms become cations, positively charged atoms, and chlorine atoms become anions, negatively charged atoms. This transfer of electrons creates big amounts of energy so a violent reaction occurs. After the transfer, the two substances change into NaCl, a new substance made out of the combination of chlorine and sodium. This indicates that a chemical reaction occurred, not a physical reaction. The last substance is commonly known as table salt.

11/08/2007

What was your favorite project, experiment or topic this trimester and why? (projectile motion, density cube experiment, podcasts, chemical reactions, flame tests, etc.) You can also comment about the snakes. What do you think that you excelled at this trimester? How could you have improved your performance in Science 7? (Make sure to check your spelling and grammar).

Entry: This was a very good trimester. I especially liked the chemical reactions. I liked it because I got to learn and see what chemicals cause certain reactions. My favorite reaction was the sodium and water. I excelled at learning the chemical reactions. I described all the chemical reactions and did all the ones I was supposed to do. I could have improved by studying more for tests. I could do this by making sets of flashcards and doing them until everything is hammered into my head.

Comment 1: I appreciate Alex's sense of humor. He is also very good in labs because he is very serious. Good job, Alex, in this trimester. I am sure you will excel. Comment 2:

12/18/2007
Our next unit is about electricity and electronics. In first person write a long paragraph about what you know about electricity and what questions you might like to have answered in our electricity unit. If you could investigate any subject area related to energy in the home, electricity, electronics, computers, etc. what would you like to research or investigate?

Entry: I’m very interested in anything related to electricity/computers/robots and all the other technologically oriented stuff. In fact, I aspire to learn the most I can about robotics and programming. I’ve learned how to build and program a basic Lego Mindstorm using the programming software and I’m currently learning how to do much more advanced programs and make my own programming language. Apart from robots, I’d like to learn about more advanced things with computers. I already use command prompt efficiently and would like to go deeper. Last, I’d really like to learn how to deal with electronic circuit boards and know where to put which wires and other basic electronic knowledge. I really look forward to next year’s (2008) electricity unit.

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1/3/2008
Our next unit is about electricity and electronics. Observe the following graph, Graph 1 and write an analytical paragraph describing what it means. Make sure to address what trends are observed; how things change over time, etc. Write at least five sentences for the following questions. Write in third person. Directly cite data and identify the graph (1). 1.) Which electricity source in the US has increased the greatest amount over the time period shown in the graph? 2.) Which of the sources listed below directly contribute to global warming? Provide evidence and explain using the Internet (MLA citation). 3.) Describe the overall trends from 1972 to 1985 regarding the US's sources of electricity. [|This graph can also be seen at this LINK.]

Entry: Electricity is what keeps the U.S. up and running. As seen in Graph 1, since 1949 to 2006, coal has been the electricity source that has seen the most increase in use. In 1949, it provided about 0.2-0.3 trillion kilowatthours of electricity. After 57 years, it has seen a major increase and now provides about 2.0 trillion kilowatthours of electricity. This is a major change, and may not be the best choice seeing as coal is a big pollutant.

Three of the electricity sources seen in Graph 1 contribute directly to global warming. These are coal, petroleum, and natural gases. These three substances are also known as fossil fuels. When these are burned, carbon dioxide gas is formed, which contributes to global warming. Cleaner sources of electricity should be found in the future.

Graph 1 clearly shows that from 1972 to 1985, coal was the most used electricity source in the U.S. It started off at about 0.8 trillion kilowatthours of electricity produced in 1972, and had gone up to about 1.5 trillion kilowatthours of electricity produced by 1985. The second most used source was petroleum and natural gas, seeing a spike at about 0.7 trillion kilowatthours in 1972 and falling to about 0.4 trillion kilowatthours by 1985. Those were the two major sources of electricity during that time. Overall, it can be seen that U.S. needs lots of electricity to keep on living, but cleaner and more reliable energy sources will have to be found in the future.

O'Driscoll, Patrick. "Fossil fuels are to blame, world scientists conclude." __USA TODAY__. 30 Jan 2007. 7 Jan 2008 http://www.usatoday.com/tech/science/2007-01-30-ipcc-report_x.htm.

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1/8/2008
Please read the paragraph below about energy use to create electricity from 1972-1985 in the US. Observe that the graph is referred to, there is an introductory statement, supporting statements are backed up with data, and that their is a concluding sentence. This would have been a well written paragraph for question 3 in our previous blog entry.

"As seen in Graph 1, there were four sources of electricity production in the US from 1972-1985. These sources were coal, petroleum/natural gas, nuclear electric power, and hydroelectric power. From 1972-1985, the US needed greater and greater production of electricity from these combined resources. This best example of this is that during these years, coal increased from 0.5 trillion kilowatthours to roughly 1.5 trillion kilowatthours. During this same time period hydroelectric sources remained approximately the same at 0.3 trillion kilowatthours. There was a slight increase in nuclear electric power sources from 0.1 trillion kilowatthours to 0.3 trillion kilowatthours during this same time period. Finally, petroleum and natural gas showed the greatest amount of fluctuation during this time period staying about the same from 1972-1980 at 0.4 trillion kilowatthours but then deceasing to 0.3 trillion kilowattthours by 1985. Thus, although greater and greater amounts of resources were needed to produce electricity during this time period, coal accounted for the greatest increase in use." - JT

//**Using the above paragraph as a model, describe the changes in electricity production sources from 2000-2005. Make sure that you reference the graph (Graph 1). Make sure all statements are backed up with data. Make sure you have an introductory sentence and a concluding sentence that provide an overall summary/statement.**//

Entry: Different sources of energy were used to produce the electricity needed for the U.S. during the years 2000-2005. These sources were: Coal, petroleum/natural gases, nuclear power, and hydroelectric power. As seen in Graph 1, coal was the major producer. In 2000, it produced about 2.0 trillion kilowatthours of electricity, and increased to end up producing about 2.1 trillion kilowatthours of electricity by 2005. The second most popular electricity producers during that time were nuclear power and petroleum/natural gas. It can be seen in Graph 1 that they produced about the same amount of energy during those years, starting at about 0.7 trillion kilowatthours of electricity produced in 2000, and ending with an unchanging 0.7 trillion kilowatthours produced by nuclear power and 0.8 trillion kilowatthours for petroleum/natural gas. The least popular producer was hydroelectric power. It produced only about 0.3 trillion kilowatthours of electricity during all 5 years. Coal has been the lead electricity producer for many years and still is today, but might not be the best choice because of its heavy pollution.

Comment 1: Overall, the paragraph was good. A problem I saw was that you did not reference your graph. Also, you were just supposed to talk about sources of electricity, not about pollution. You used good grammar and spelling was correct the best I could see. You also referenced data from the graph even though you did not reference your graph. Your content was well thought out and very true. Great job, Alexandre.

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Re-Entry: Different sources of energy were used to produce the electricity needed for the U.S. during the years 2000-2005. These sources were: Coal, petroleum/natural gases, nuclear power, and hydroelectric power. As seen in Graph 1, coal was the major producer. In 2000, it produced about 2.0 trillion kilowatthours of electricity, and increased to end up producing about 2.1 trillion kilowatthours of electricity by 2005. The second most popular electricity producers during that time were nuclear power and petroleum/natural gas. It can be seen in Graph 1 that they produced about the same amount of energy during those years, starting at about 0.7 trillion kilowatthours of electricity produced in 2000, and ending with an unchanging 0.7 trillion kilowatthours produced by nuclear power and 0.8 trillion kilowatthours for petroleum/natural gas. The least popular producer was hydroelectric power. It produced only about 0.3 trillion kilowatthours of electricity during all 5 years. Coal has been the lead electricity producer for many years and still is today, but might not be the best choice because of its heavy pollution(MAY WANT TO PROVIDE A REFERENCE HERE. GREAT JOB- JT

2/05/2008
What is a watt? How do you calculate the amount of electrical power that is used in a circuit? Finally, if a lamp with a 200 watt lightbulb burned for 24 hours straight (you forgot and left it turned on), how many kilowatt hours would it use? Make sure to write in complete sentences and in third person. Explain how you calculated the amount of kilowatt hours that would be used in the question above.

Entry: A watt is the measure for electrical power. To calculate the amount of electrical power in a circuit the current and the voltage must be multiplied. Most electric companies use kilowatts to measure how much electricity is sold. If a 200 watt lightbulb kept on burning for 24 hours it would use 4.8 kilowatt hours of electricity. If one kilowatt is 1000 watts, the lightbulb uses 1 kilowatt of electricity every 5 hours since it uses 200 kilowatts per hour. Twenty-four divided by 5 is 4.8, so the answer if 4.8 kilowatthours. It's not very hard.

Comment 1: Very good Alexandre. The paragrpah was very well written. You showed an understanding of watts and how to calculate kilowatthours. This is hard to write about because it is so good, there is nothing wrong with it. Great job Alexandre.

Comment 2: Great work Alex! There were a few simple things that would make a better paragraph if changed. In the second sentence, it might be in your best interest to use units for voltage, power, and current. The last three sentences were a bit confusing because the 1 kilowatt for every 5 hours came out of no where. The last sentence was also weak, "It's not very hard" - you might want to rephrase this or just delete it. In the end you found the correct answer although the means were a bit confusing. Great job! :)

-Rachel

2/28/2008
This trimester we started by finishing up our chemistry unit by doing an acid/base experiment. After this, we started our electricity/electronics unit in which we first made basic series and parallel circuits with buzzers, speakers, motors, and lights. We applied ohm's law to these experiments. Following this, we started working on the Radioshack Electronics Kits where we made complex circuits that had a variety of functions- blinking LEDs, screeching speakers, analog to digital converters, etc. The technology we used this trimester included the pH probes that we connected to our computers to get the pH of household chemicals, using the wiki to create an class test review sheet, the Radioshack Electronic Kits, and creating collaborative lab reports in the wiki for our electronics unit (instead of a formal lab report).

//__In this blog prompt, please write a paragraph long entry (5-6 sentences with a intro and concluding sentence) that addresses what you enjoyed during this trimester and what you have learned. You can also comment on what you would like to improve upon for next trimester or what was difficult for you. Feel free to comment on our snakes- Peppermint and Diablo if you would like to as well as the technology that you enjoyed this trimester. Please check your spelling and grammar as this blog entry may appear in your end of trimester comment. You may want to write it in Microsoft Word to check the spelling, etc. and then copy it in the blog.__//

Entry: I pretty much liked everything we did this trimester. I especially liked the electricity unit. I learned that it was much harder than I thought to make a working electrical circuit using a breadboard and wires, but I was still able to build a complex digital to analog converter with my partner Adam. I don’t know what I should improve upon, but I’m sure I will find the answer to this question next trimester. Science has been fun this trimester and I hope this will continue for the third and last trimester.

Comment 1: Alexandre is kind, funny, and enjoyable in any situation. he has been a great friend, and is always willing to help someone. he is a great person. Jackson

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4/22/2008
Go to: [|The Tech Museum: Robotics]. Spend 10 minutes browsing the information and museum. Answer the following blog prompt in complete sentences and in third person. Create a full paragraph. If in the future machines have the ability to reason, be self-aware and have feelings, then what makes a human being a human being, and a robot a robot? Explain. Are there any kind of robots that shouldn't be created? Or that you wouldn't want to see created? Why?

Entry: There is, and always will be, a huge difference between robots and a human. That difference is: the material they are made of. Robots are made of electrical components, humans are made out of living, breathing organic material. That is probably the main difference. Humans actually **live**, meaning they need other living organic material to keep on living, while robots just need their daily dose of electricity to keep on going. There aren't really any robots that shouldn't be made. People say that military robots shouldn't be made, but this isn't true, armed robots can be helpful in many ways, there just needs to be an easy way to turn them off. This is a good idea for any robots. Mechanical components can always go wrong, and an easily accessible way to turn off a robot, such as a remote, is a good way to prevent any problems.

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