# Tag Info

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Since both are at the same temperature, both have the same degree of hotness ie. Temperature, hence similarly cold or hot. The difference is that water and ice both have different enthalpies, Water when converted to ice requires only phase change enthaply(assuming water to be at 273K), the enthalpy of freezing is then, Q(f) = ml

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The one that absorbs more heat from you will cool you more, and seem colder. But it isn't entirely straightforward. If you pour water in your hand, water will flow to fit you. An ice cube will not make as good contact. Water in contact with you will warm. It can then flow away and be replaced by fresh cold water. Ice doesn't flow On the other hand, Ice ...

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The Kelvin temperature scale is an absolute temperature scale. That is 0 K is absolute zero. It also has the property that temperature intervals on the Kelvin scale are the same as on the Celsius scale. That is a decrease or increase of one degree Kelvin is the same as a decrease or increase of one degree Celsius. To meet these two requirements it is ...

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Since the heat capacity of water is 10x that of steel, the same energy input to equal masses of steel and water will raise the temperature of the steel 10x more. So to raise a certain mass of water from 0 °C to 100 °C (boil it) and raise the same mass of steel from 0 °C to 1000 °C (melt it) will take approximately the same amount of time, assuming the same ...

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As a physics problem in a textbook, you could get somewhat close. Both the water and the steel have a heat capacity that relates the amount of temperature rise that would accompany an input of energy. If you make a few assumptions, you can relate the two. The problem with a real-world application is that those assumptions may be far from valid. The two ...

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Paper is made of many, many tiny fibers. When you wet a piece of paper, those fibers absorb water and swell up. As they dry, the relaxed fibers don't go back to exactly where they started. Some will have shifted or "untangled", moving out of the plane of the original paper. So yes, the paper actually does become slightly bigger because the fibers have ...

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The air in the freezer is a poor conductor of heat. The greater surface area of the porous paper along with its heat conducting water allows it to act as a heat sinc. It transfers heat from the liquid to the glass or aluminium and then to the water in the paper which sheds the energy by conducting it to the surrounding materials such as the air and the ...

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Others have explained the physics. I just want to add that those of us with low body fat can become negatively buoyant at the surface if we breath out and empty our lungs. I can sink down and sit on the bottom of a swimming pool. So it is very possible to dive to a depth where you have negative buoyancy but what depth that will be will depend on the density ...

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Yes. a wave created with a certain frequency in the water remains the same even if the medium is changed. The only thing that is important in here is the amplitude of our wave. When the sound wave from inside of water hit the surface, some of the wave reflect back into the water and a lower amplitude wave is continued in the air. so the energy of the wave ...

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What you see is the escape of dissolved gases in the liquid. Water in a cup in a microwave heats fairly uniformly; by contrast, if you heat on a stove, you hear the water "sing" because you get local boiling of the water that is right next to the wall being heated. During the "singing", dissolved gases are driven out (and they don't really re-dissolve - but ...

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To a reasonable approximation steam at 100°C can be treated as an ideal gas. The molar volume of an ideal gas is 22.4 litres, so at 0°C (273K) and one atmosphere 18g of steam occupy 22.4 litres or in more useful units 0.018kg occupy 0.0224 cubic metres. You can work out the volume at 100°C (373K) using Charles' Law, and then calculate the density of steam at ...

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Ice cubes are colder than the water they are in, so the water freezes the two ice cubes together forming the bridge with the ice.

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It depends. Your elders probably meant an approximation in that the relative change is so small that you can neglect it for all practical purposes. I didn't do the calculation, but just make this back of the envelope calculation. The volume of the oceans is $1,335,000,000 km^3$ or about $1.3 10^{21} liters$. If you include one member of each species, the ...

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Um. This is an odd one, I think. It is simply not true that the amount of water in the ocean is always the same. In fact, the amount of water in the sea (well, also the volume of water--thermal expansion) has been increasingly lately and is forecast to increase in the future. It is true that there is SO MUCH water in the sea that we can remove a lot of it ...

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First up thanks to all who took an interest especially @irishphysics who stuck with the question for some time. It turns out that the phenomena was analysed and solved by Lord Kelvin and is known as the Kelvin wave pattern. The pattern itself is the result of a spreading pressure wave which manifests itself as the curved diverging wave crests (the ones I ...

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I will focus on just a little bit of one of your questions - the relationship between compressibility, density and pressure - and per my comment, recommend that you narrow down the scope of your question. As you know, in a gas we experience "pressure" because molecules hit the walls of the containing vessel. When I double the number of molecules in the same ...

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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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Most likely what you are seeing is a thin film of oil floating on the surface of the water that comes either from natural underwater sources, runoff from the shore, or from ships. The oil breaks the surface tension of the water and reduces traction forces from the wind - thus ripple amplitudes are reduced or entirely diminished. This phenomena has been ...

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I've also seen this, and wondered what it is! I thought they may have been some sort of surface currents as they looked like "rivers" to me. However, I've just done some searching and found this and this. So the answer is biogenic slicks, oily substances exuded by algae washed off from the shore! These don't dissolve well with water and form a thin film over ...

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