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Showing results for tags 'heat'.
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It's common knowledge that a blue flame is hotter than a red/orange frame. While I'm not entirely sure that is true, having never tested the fact with my own appendages, many reliable sources seem to say it's true. But why, really, is a blue flame hotter? The answer lies with a bit of science on the nature of "light". Light with higher frequencies (towards the blue/violet end of the spectrum) contains more energy than light towards the other end of the spectrum, the red/orange end (light in this case refers to all electromagnetic radiation - from gamma to radio waves). And when objects are heated, they radiate energy in the form of light. As you can see in the attached image, this pattern of radiation follows a predictable function dependent upon temperature and wavelength. While certain materials emit certain wavelengths better than others, the general trend is that, the hotter the object the is, the more power it will output at higher and higher frequencies. In other words, a blue flame is emitting more energy at higher frequencies because it is hotter. Theoretically, purple flames would be even hotter, and would most certainly look cooler. The big lesson is that there are plenty of ways to quench your curiosity about flammable objects with your eyes, and not your various limbs. Although I guess you can always try.
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The drinking bird novelty item has been around for decades, but it's seemingly simple design is deceptive. Carefully calculated physics principles have gone into the creation of this toy. Mostly, it utilizes energy conversion, operating as a heat engine that changes heat energy from water into mechanical work. The drinking bird design is made up of several important components: -two glass bulbs of equal size attached on either end of a glass tube -a fuzzy, absorbent material to cover the bird's head -two plastic legs connected to the body with a pivot -a small amount of methylene chloide (industrial paint stripper and solvent) liquid in the bottom glass bulb -either a red or a blue hat, depending on the model For the toy to work, the felt tip on the bird's beak must be dipped into a cup of water, which then allows it to absorb a small amount of that water. As the water in its beak evaporates, the temperature in it goes down, which causes the methylene chloride vapor to condense. When this happens, liquid from the bottom bulb is forced upward, toward the head and beak portion. Then, as liquid enters the head, the bird becomes top-heavy and slowly begins to tip forward once again. As the drinking bird does tip, the rest of the liquid goes to the bird's head and the bottom portion of the tube isn't submerged any more. Vapor then travels back up the tube which will then cause the head to drain of liquid again. As the bottom glass bulb is filled with liquid again, the bird becomes more bottom heavy and the entire process begins again.
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