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If the coffee is cold enough then it will make a layer of whipped cream, which is basically a mixture of sugar and coffee. The thing is that the layer becomes sticky at the surface while the coffee is liquid beneath and flows in the lower layer. The liquid flows because the lower layer is not dry enough and sticks at the surface to resist the liquid layer ...


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layman, It takes more PSI to suspend a heavier load with equal square inches. Or the same PSI with more square inches. Rubber tires will mostly just flex to give more square inches. Foot print of tires x psi = weight of car


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For the record, it might be a partially blown head gasket letting water flow from the coolant channels, into the combustion chambers, and out the exhaust. A lot of water flowing out of the exhaust isn't normal.


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If you want to smash another person's egg, you simply need a firm grip around the base of the egg (the wide end) and attack with the narrow end of the egg pointed at the other person's egg. The science behind this is the physics of pressure $$ P=F/A $$ P for pressure, F for force and A for area. When the narrow end of your egg hits the side of another egg 2 ...


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Well, it doesn't burn faster. I would say it burns slower but tans faster. Thats how dark tan oils work. The melanin absorbs the energy from the sun to charge and store it. The body wants more and produces more melanin. So you would get dark. However I believe the water on the skin just intensifies the energy, not the burning uv ray itself. Therefore, I ...


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1) The $sin$ term appears to be resolving the velocity of the water relative to the face of the disk. $U$ is the just the speed, it's necessary to determine what part of that velocity will produce force on the object. It might help to visualize extreme cases, setting $\alpha$ and $\beta$ to 0, $\pi /2$ etc. For $\alpha = \beta =0$ you have a perfectly level ...


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Instead of the word light it would be better to use the word electromagnetism. Newton and Young were fascinated about the decomposition of white light into it colors and about fringes behind edges. Since Maxwell it was obvious that light was only a small part of the electromagnetic spectrum. Later were discovered the weak and the strong nuclear power. But in ...


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Light exists in nature therefore physicists were bound to be interested in it at some point. But light is special in a sense. All we see, we see with light. Our eyes are sensitive to electromagnetic fields which make up this light. Furthermore, the main force which keeps the stars together is electromagnetism, which is the interaction of matter and light ...


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Light is a rare phenomenon as it has no mass. Most particles have mass and therefore cannot act in the way that light is, which is to move at the speed of light. At this speed, due to relativity light moves at the same speed regardless of your perspective; no matter how fast you are able to move you can never catch up to light, and even as you try harder to ...


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The ratio of the circumference of the body and the hulahoop (HH) is an important parameter. The greater the ratio, the more the HH will rotate - and the more it rotates, the greater its angular momentum. When you have an object spinning with its axis vertically, and apply a torque, it will precess - instead of falling in the direction of the torque, its ...


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It has more to do with physiology of the eye rather than the spectrum of light produced by stars. Stars emit light over the full range of visible wavelengths. Hot stars emit more blue/violet light, cool stars emit more red light. The Sun is relatively neutral in that regard, so does not have a strong colouration, but many other stars in the sky have ...


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Short answer: Many of them are not. Stars can be modeled as black-bodies. That means that the spectrum of light that they emit depends on their temperature, and the color of a star can be described as its Color Temperature. The color temperatures of stars can vary quite greatly, because stars have very different temperatures and emission spectras. One of ...


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The sun is white. I've seen people say that it just looks yellow because the blue light is being scattered by the atmosphere. Since starlight is also scattered your question is still valid. But based on these pictures, the sun still seems to look pretty white through our atmosphere. My guess is that, since you can safely look directly at a star, you learned ...


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Our sun is actually white. Sun seen from space. It's just that when the sun rays enter the earth, our atmosphere scatters the white light resulting in different colors. The reason why the Sun appears to be white sometimes is usually because it's directly overhead. Then the rays coming from the sun have to travel the least distance and hence encounter less ...


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The wobble is the result of creating an oscillating system. At a perfect equilibrium, your tower would stand straight up and down, at rest, with a net force $\Sigma F$ equal to zero. However, as you remove blocks, you are imparting a force on the tower, and disturbing the tower from equilibrium. If that was the end of the story, your tower would continue ...


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When you rock the espresso from side to side you make the surface larger and stretch the bubbles. When the surface comes back to its original size it is energetically more favorable for the bubbles to bunch (lowering their exposed surface area). Every time you rock the cup, the thinner region is stretched more (relatively) and so the bunches end up ...


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Informally, by the cumulative effects of friction when pulling out a piece (hence dragging it) and vibration of your hand when pulling out the piece (noticeable even with skilled players, however minute), you disturb the centre of gravity of the structure (by making the structure tilt),- making it subsequently topple because it is made of stacked pieces and ...


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The trick is here in the temperature of the pot. As you know, evaporation does not require boiling at 100°C: else, towels would only dry in an oven, and as far as I know, nobody dries towels in their ovens. Instead, it depends on the partial pressure of water vapor near the water surface (as Hot Licks mentioned). If the lid is on the pot, the partial ...


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No, in general they do not. You can work this out from the geometry of Ackermann steering, discussed on my website article "Parallel Parking a Car". In summary: look at the defining geometry for Ackermann steering, which I have sketched below: Ackermann steering is defined by the intersection of the central unit normals to (axes of rotational symmetry ...


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Polyvinyl alcohol is the material used to make the water-soluble packing. The water molecule is polar (negative at one end and positive at the other). This nature of water allows it to pull the Polyvinyl alcohol molecules apart (which is usually how dissolving works).


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If you want to get technical, check out steam tables such as found on:http://www.engineeringtoolbox.com/saturated-steam-properties-d_273.html Putting the lid on the pot will slightly raise the pressure inside the pot, therefore the boiling point will raised. The steam generated will be under somewhat higher pressure. When this happens the latent heat ...


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This is the sort of question which is easily answered by actually doing the activity in question instead of looking at it and scratching your head. And when you actually do heat the water you will find that yes, the time to get from room temperature (for example) to boiling is shorter with the lid on the pot - and noticeably shorter - than without. Also, ...


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On the subject of cooking, someone once told me "If you have too much water in your pot after cooking a dish, just turn up the heat and let it boil without a lid for a few minutes". That acquaintance was absolutely correct. There are a number of ways to cheat and quickly thicken a sauce, but (a) this is cheating, and (b) the sauce doesn't taste as good. ...


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When cooking, keeping the lid on a pot does a few things if you think about it: it decreases air circulation significantly so the air in the pot stays hotter, this cooks the food faster. if it's snug, it should increase the air pressure.* The pot lid captures condensation, so it will return water back into what you're cooking. That is, I think, the ...


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The lid increases pressure, and liquids under higher pressure have a higher boiling point.



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