Kauffman,+Lydia

I read the article "Dust Explosion." Since I am allergic to just about everything, when I saw the word "dust" I thought the article would be interesting. To summarize, the article was about combustable dust that is most commonly found in factories and plants. This dust collects on floors, beams, and windowsills in the plants with minimum attention from the workers. What the workers don't know is that the dust may be explosive. Once some of the dust has already ignited, even by static electricity, it can stir up other dust that has collected in the factory causing a chain of explosions. In the article, a sugar plant had burned down because of the explosive dust. Nine workers died and 16 were seriously injured in the fire. As stated in the article, it is hard to think of sugar as being explosive, but there was no escaping the "balls of fire" that moved through the factory. As the article was written in 2008, it makes me wonder what if anything came about by either OSHA or CSB in regard to regulation of factory "dust?" I believe that with the seriousness and the number of fatalities that have been attributed to this problem that there should be an increase of factory and plant inspections specifically having to do with exploding dust. I also learned from this article what the word conflagration means; great fire.

I read the article "Trick Candles " as another article. I love trick candles at birthday parties! In the article people are saying that trick candles should be banned in the US, just like they are in Canada. I have to disagree with that statement. It would be complicated to stop the use of these candles. Also, It would cost money to stop production and spread the news of the huge hazard the candles poses. I think the candles bring some humor into birthday parties and should be kept legal in the US. Also, it would take a while for the news to circulate around and stores to stop selling the candles. I agree that the producers of trick candles should warn the public about the fire hazard and that is the best thing they could do for public safety. I can see how the companies would be concerned but there is no need to stop production. I also have to comment on how amazing the Chemistry is for these tiny candles. You would never think about trick candles as Chemistry! I know I didn't! I just thought they were neat little things to make the birthday girl/boy laugh. I would like to read more information on these candles and know more about the Magnesium and all the other chemicals and how they work together.

Lydia, Good job! Good comment on magnesium. BTW it's Chemistry not Chemestry! :) 5 stars. MW

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Redefining the Kilogram

I found this article very informative. One point that I thought was kind of odd was the fact the the international prototype of the Kilogram is kept in a highly secured vault in Paris, of all places. Since the SI unit system in french, is that why it is kept in Paris? I also found it very interesting that the Kilogram is the last of the SI units that is still defined by a physical artifact. I would think that it wouldn't be as much of an artifact as it is a model. The last thing that I was surprised about is the fact that the standard Kilogram has changes its weight over the last several years. I would think that the scientists would do everything in their power to keep that from happening. But, is there a way to keep that from happening? Is the metal it is composed of at high risk for weight change? But, all-in-all I found the article very interesting and I learned a lot about the standard Kilogram.

Lydia, Apparently the metal had some radioactive isotopes in it that decomposed over time. At least that was one hypothesis I heard. Good thoughts! 5 stars. MW

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Motion Detectors

I found the article pretty interesting. I do not have the motion detectors at my house but I see them around my neighborhood. When the article was mentioning the different ways motion detectors work there was one talked about that I found different. I was surprised to see that some motion detectors use a light sore (infrared radiation) aimed at a photo sensor. Is this kind of like a light beam? The way the light source motion detectors were described it reminded me of garage doors and the lasers at the bottom (that stop the door if something gets in the way). Is it the same thing? The next thing I found interesting in the article is the fact that some other motion detectors use infrared radiation to detect a change in the heat. With increased heat and energy the spotlight goes off. With all this radiation wouldn't some of these detectors be harmful? The last thing I found thought provoking is there are so many ways that motion sensors are used in everyday life that we don't even think about. For example, stores that have a bell "ding" when you walk into the store but not when you walk by it. Also, automatic doors. All these things we take for granted but in reality it all has radiation and chemistry behind it.

Lydia, Looks good! You touched upon a common misconception - that radiation is always harmful. Some electromagnetic radiation is quite low energy and harmless. 5 stars. MW