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Lots of poor info here. Ribs are not an impenetrable barrier, compression happens between them. Fat can also be compressed so is not bouyant. Equalization of bouyancy for humans happens at approx 4m below the surface. So jumping off a medium height bridge into water 'just to cool off' means you won't get to the surface unless you swim upwards.


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If you place water (or other material) in a pressure-tight container, the water will change as heat and pressure cause its molecules to become more or less energetic and the bonds among its molecules to become more or less stable, or begin breaking apart. These changes are summarized in a chart called a phase diagram. Here is a simple phase diagram for ...


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EDIT#2: I'm now made aware that you need wavelengths that are much larger than those presented here(a bit of an oops from reading this question quickly). This approach is still valid, but what you need cannot be obtained from these data. I'm going to leave this here however to collect downvotes and if anyone needs $\epsilon_r$ as it depends on $10^{7}$ to ...


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This phenomenon is due to the presence of air bubbles in the water. First note that the solubility of air in water decreases as temperature increases. Therefore when water is heated, less air can be dissolved in the water and when the water leaves the highly pressurized pipes, the air within the water is able to form bubbles and escape into the surrounding ...


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You don't say what the ash is from, but fine ash is a flocculate of very small particles. As such, it has a very low density with air entrained within it. When you add water the capillary forces produced by the water collapse the structure and expel the air trapped within it. The emerging air carries particles of the ash, hence you see puffs of ash as you ...


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I have done some builded shots with Vodka and Ice in a -18 C degrees. And because I don't have fotos or links, I just tell you how it goes; 1. Put a bit water on a shot glas and let it freeze. -18 C 2. Put -18 C Vodka (I actually used Amaro del Capo) in the glass above the ice. -Let it stay. What happens? First, the vodka melts the ice and forms a snow ...


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By heating the liquid the heat energy absorbed by the molecules and then it tends to vibrate more compared to its ground state. Due to the heavier vibrations the atoms moves more far apart from its equilibrium position. Now the phenomenon called "phase change" occures. Then the liquid is transformed into gaseous state.


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if it was a plastic cola bottle it is because the plastic is a cross linked polymer, and is designed to be heated and then pressurized into a mold, and cooled under pressure to maintain its shape. this particular plastic was chosen because of its low failure rate in this process ( holes and deformities ) it is very much the same as heat shrink tubing or ...


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The water heats up and expands as it is falling through the oil, due to density. the water is covered up and expands into steam blowing the oil away. boom.


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The bond that holds water as a liquid is a simple static electricity bond. it has a strength and will 'break' with sufficient energy. this happens all the time. water evaporates, when a random chance of circumstances through thermal agitation and exterior pressure are at the right amount the molecule leaves the liquid and goes flying off as a gas. the higher ...


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Warmer water will tend to bond faster but in a more disorganized fashion. Molecules at a temperature closer to the 'freezing' point will take more time to bond but the packing fraction will be more efficient. This is the same philosophy behind crystal manufacturing. The Bottom line is that under the same exact conditions warmer water will make ice faster ...


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To answer your questions, would a 90 degree shot turn the ship, in theory yes, due to the conservation of angular momentum law. As long as the cannon was not exactly amidships , in which case it would push, or more probably just cause a list, to port or starboard. And would a 180 degree shot (aftwards) increase the speed of the ship, again, in theory ...


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Other answers are right, but let me put it without math: Water can't come out of the bottle if air can't go in. (Except: if the water in the bottle is so tall that water can come out even if air can't go in.)


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Water stops draining from the jar into the dispenser once it forms an interface as draining of more water would result into the formation of a vacuum in the jar because no air can rush into the jar to displace the water as it has an interfacial-lock. Consider the water level above interface $= h$, water level below interface $= x$ now $$P_{surface}= ...


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Sewage drains in houses should always have a "vent stack" - piping which extends up through the roof. The vent portion of the sewage plumbing has two purposes: to allow gases in the system to escape, and to provide a "suction break" so that traps (U-bends) don't have their contents sucked out when the pipe fills with flowing water (the water in a trap is ...


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All water molecules do absorb infrared radiation (contributing to the greenhouse effect), but the phase of the water molecule does influence how effectively it absorbs radiation. If you look at this graph of water's absorption coefficient: (http://t.co/SP3RyofTug) You see that clouds are represented by the red line (water as a liquid). Water vapor is the ...


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This scheme would be terribly inefficient thermodynamically. Firstly, where is the energy needed to generate the electrical pulses coming from? Secondly, neither the process of electrolysis of seawater or the combustion of the resulting hydrogen and oxygen is 100% efficient. Finally can this system really generate enough thrust to propel a boat? If the ...


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The energy required to split the water into oxygen and hydrogen is quite a bit less than the energy you would get back when you burn it (commercial electrolysis units run at about 70% efficiency). I think that makes this an inefficient method of propulsion. If you just (electrically) heated an amount of water until it became steam you would reach the same ...


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I tested it against a control and it worked. Used longneck glass bottles. Didn't measure the difference but the difference was notable to the touch after half an hour.


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Contrary to popular misconception, below a specific temperature, glasses do not flow. At all. A glass by definition is a solid sans repeating crystalline structure. Anything which flows (see "pitch-drop experiment which drops every 80 (or something) years") is a liquid, however viscous. Liquid glasses tend to have reasonably high viscosity, but once ...


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As stated in previous answer,many things happen in water ripples.But a major reason for increment in wavelength is loss of energy as the wave progresses due to non ideal conditions.Since wavelength is inversely proportional to energy of wave,as energy decreases,wavelength increases.Hope this helps :-)


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Several things happen with ripples. First - they are comprised of different wavelengths. That may be hard to explain in plain English, but basically the only way that a wave can have a single wavelength is when it goes on for all infinity. A short "wave packet" must contain different wavelengths. Next - the speed of propagation of these different ...


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In the short term, the sloshing of the water as you not-completely-cleanly let go of the bottle will be the dominant effect. In the long term, since you're ignoring air resistance, and if we assume the bottle isn't spinning in any way, then surface tension will dominate. Different material interfaces have different energies, and absent other forces those ...


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I did a little reading and my understanding is that explosions underwater at the same distance as one in air will be much more destructive. Water is a much denser medium than air allowing for the shockwaves to propagate faster. The initial shockwave will be followed by a blast of water, again delivering more force than a blast of air. An interesting ...


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When plastic bottles are made they start with something that looks like a test tube with the threaded top for the bottle cap. It's heated and air is blown into it while it sits in a bottle shaped mold. Then it's quickly cooled to lock the plastic into that shape. The stretching creates residual stress in the plastic. It wants to un-stretch like a taught ...


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A liquid / gas mixture in an enclosed vessel in a zero-g environment can be quite weird. Given enough time, the contents of the tank eventually become an ethereal mix of blobs of liquid, bubbles of gas, and foam. This creates a significant design challenge for liquid fuel tanks intended for use in space. One solution is to use a bladder to separate the ...


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The environment in a free-falling object is the same as one without a gravitational field (neglecting gradients in the gravitational field, i.e. tidal forces). So, before you drop the bottle, gravity is holding the water at the bottom and creating a slight air pressure gradient between the top and the surface of the water, and a water pressure gradient ...


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If you drop a bottle without any residual motion (that is, it is not spinning etc) then everything inside that bottle will be in "free fall". The air and the water will attempt to fall at the same rate. There is a nice video of what happens to water when it "spills" in the International Space Station: it becomes a "blob" because of the surface tension. Add ...


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Fill a garden hose with water. Hold both ends closed, and walk to the "higher" pond. Have someone helping you hold the end of the hose under water. Now walk to the other pond (still holding the end of the hose shut). Hold the hose near the surface of the pond - you should feel water pressing against your finger. Make a very small opening and observe the ...


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I think nothing. Example #1: Calculate the rms speed of an oxygen gas molecule, O2, at 31.0 °C Solution: $v=\sqrt{\frac{3RT}{M}}=\sqrt{\frac{3 \times 8.31447 \times 304.0}{0.0319988}}=486.8 m/s$ That is pretty high average speed of oxygen molecules. The acceleration of the bottle does not change it much at beginning. The direction of molecules motion is ...


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Looking up "what happens when lightning strikes a house" on google (it is a .php file so I had to use printscreen) See also this youtube video. So yes, avoid taking a bath during a close by storm. Have a look at this answer What will happen when lightning strikes on the surface of the deep sea? which has some numbers of the energy in a strike. By the ...


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The reasons you are looking for (why it doesn't work) are twofold: First, mass. Bullets are made out of lead, tungsten, depleted uranium etc. Heavy stuff. Aluminum and brass would make perfectly good ammunition if they weren't so light (or if the shootout was on the moon). The problem is lighter projectiles are greatly affected by air resistance and lose ...


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It's not feasible, this was tested by the MythBusters (assuming that a frozen blood bullet would be similar to an ice/meat one): http://mythbustersresults.com/episode1


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Tricky with a typical explosive propelled bullet but if you have a compressed air gun handy then it's quite easy. It is even the subject of a long lived Urban Legend


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A will lose heat faster. Conduction and convection scale as the temperature difference, which is almost twice as large for A as for B. The warmer water in A will also evaporate faster, removing more heat as it does.



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