Questions tagged [water]
Two Hydrogen atoms covalently bonded to one Oxygen atom. One of the more common compounds on the surface of the earth.
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Temperature of a resting glass of water
It’s summer and summers have become more and more hot&humid lately. This got me curious about the dew point and then wet bulb temperatures, both for scientific and (maybe, someday in the future) ...
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Albedo of water vs temperature
This question arose out of pure curiosity.
Is there a relation between the temperature of water and its albedo? Would the albedo increase if I increased temperature? Say I measure albedo by directing ...
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Why won't there be any transfer of heat energy when ice at 0°C is in contact with water at 0°C in a closed container?
In my book, Concise Physics of Selina Publications for Class IX, it's written there that "If there is no transfer of heat between the two bodies placed in contact, they are said to be at the same ...
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Pressure build inside water tank [closed]
It‘s been a few years since I had my last physics class so please be kind to me. I came here to ask you about a phenomenon I recently discovered in a design of mine.
The object in question is a stand ...
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Can siphons improve the efficiency of hydroelectric dams?
Suppose we have built a hydroelectric dam where the water inlet is 100m above the outlet. We can now use the gravitational potential of the water to spin a turbine. However, suppose we install a ...
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Energy Benefits of Using Windows Vacuums to Remove Water That Otherwise Evaporates and Absorbs Energy
I've been using a new window vac and pondering its effect on the temperature in the house - and there seems nothing written about this that I can find. Plainly when the water evaporates energy is ...
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Why rain drops are spherical while water droplets on a glass surface are flat?
Why are raindrops spherical when falling through the air, but lose their spherical shape when they are on a flat surface?
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Does Pipe Temperature Directly Correlate To Water Temperature? [closed]
I need to know if just by taking a boiler flow pipe temperature that will tell me the water temperature that is flowing through the pipe.
For example if the water from the boiler travelling through ...
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If I'm inside water, is the amount of heat energy I can receive capped because water can't go above 100°C?
I just learned about double-boiling, where instead of putting a pot directly on the flame stove (where it can get too hot), you put a big tub of water on the flame, and put the pot in the tub of water....
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Intuition about SCAN-DFT
I am currently performing molecular dynamics simulations of water/ice and would like some intuition behind some of the results I am seeing. For context, I am using the water model described in this ...
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Drying polymers (e.g. FDM 3D printing filaments)
As far as I understand, a polymer absorb some moisture and amount of (maximum) moisture that can be absorbed depends on its type (PLA ~1%, ABS? ~10%). Both simple commercial filament dryers and drying ...
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Velocity Needed For Water To Overcome Adhesion Force To A Rounded Steel Inclined Plane
Context: I work at a fast food restaurant with a 3-module sink. The sides are slightly angled down to allow the water to trickle down into the compartments. I found that water clings to the side of ...
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Earthen Pots made in summers vs winters
I've heard my parents saying that the water in earthen pots that are made in winters cools more than a pots that are made in summers. Is this true according to physics? I understand the process of ...
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Rotating a Pot of Boiling Water on a Stove
I have just boiled a half dozen eggs and wanted to ask about a phenomenon I have witnessed for years but have bottled up inside for so long. Why, when the water is near boiling and nice and hot, does ...
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How do bubbles on water surface merge?
When we open a tap over a water surface, we get to see a lot of bubbles ("half merged in the water") coming out on the surface.
Now what I saw was that two such nearby half bubbles merge to ...
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Why does $\rm{H_2 O}$ have 12 degrees of freedom?
I know there will be 3 translational D.O.F. and 3 rotational D.O.F., and it can have 4 vibrational D.O.F. (one potential and one kinetic) for each O-H Bond. But from where does 2 more D.O.F. come from?...
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Water and ice, scales [closed]
There are scales with an identical bowl on each pan. We pour some amount of water into the first bowl. We pour less water and put an ice cube into the second bowl so the level of water in both bowls ...
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How long for boiling water to cool down in a cooler?
I have no knowledge in physics but I drink green tea, and it requires water at 70 degree (so does the package say). My boiler can only heat to 100 degrees (not below), so I would like to know how long ...
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Difficulties understanding fluid flow claims in the context of animal physiology/cardiovascular networks
A topic that has repeatedly given me confusion is the notion of fluid flow through animal vasculature. I find that many of the 'physics 101' basic notions of fluid dynamics are not well-suited to deal ...
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General Doubt. My doubt about combustion
When we give flame to a newspaper it burns readily. What we need for a fire (fuel, heat, Oxygen) is also known as the fire triangle. But why does the paper not burn when we pour boiling water over it? ...
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Keeping sparkling water inside a bottle as aerated as it was before opening bottle
So when you open a new bottle of sparkling water (or soda) it's very fizzy and aerated. However, when it is stored for quite a bit (no matter how tightly you close the bottle cap) it loses some gases ...
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Apparent position of object in bowl of water
Say you have a bowl of water and you keep an object in it. What would the apparent position of an object inside the bowl from the position of an outside observer? Will the curvature of the spherical ...
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Does having a liquid (less dense than ice) above a floating (in water) ice cube, change the fact that the water level remains constant when ice melts?
An ice cube floats in water, with a liquid (less dense than ice) above it. When the ice cube melts will the water level go up, down or remain constant?
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How long to put Silica gel in microwave oven?
I have a 800 W microwave oven and want to dry some silica gel packages (each labeled with 10 g and sealed in paper mantling).
The silica gel is colorless and seems to be of the kind of silica gels ...
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Does the specific heat of water vary with pressure?
I know that there is both a Cp and Cv value, but here's what I don't understand: are they independent of what the absolute pressure is? They vary with temperature, and tables can be readily found with ...
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Best mesh design for a tea strainer [closed]
I'm currently designing a closed tea strainer / egg made of stainless steel and testing a prototype made of polycarbonate plastic. The problem I'm facing likely has to do with the capillary effect - ...
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Can latent heat exist when both phases cannot exist at same temperature?
This is my understanding (please tell me if i am going wrong anywhere):
During phase change (i.e. ice melting into water) the molecules absorb heat, gain more random kinetic energy, and spread apart (...
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For a liquid at boiling point, how can it require a set amount of heat (latent heat) to vaporize
I've always had a hard time wrapping my head around the 2 below statements being true for vaporizing a liquid into a gas:
When a liquid reaches its boiling point the temperature stops rising (and any ...
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Peltier Thermoelectric Module - Water Cooling
My questions concerns calculations about a Peltier Thermoelectric Module for the cooling of water between an inlet and outlet. The Peltier water cooling module I am referring to is the following: ...
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Why does laser light not bend (refract) when it travels from air to water?
I passed green laser light from air to water but to my suprise the light doesn't bend towards normal even though I changed the angle of incidence.It goes undeflected ,Is it because of its higher ...
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Why does the freezing point of water regress at select pressures before increasing again at even higher pressures?
This phase diagram of water shows how the phase of water is determined by the pressure and temperature.
I find it easy enough to understand; as the pressure increases, the boiling point of water also ...
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Capillary action strength questions [closed]
I've been studying capillary action, and I've drawn some conclusions about the behavior which surprised me, and I want to know if I'm understanding it correctly.
According to Jurin's law, the height ...
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Conservation of water?
I know that water can exist in various states (liquid, solid, ...) and can be in various places (clouds, oceans, ground, ...). What I want to know is whether or not the total number of water ...
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Why do water surfaces have persistent "average wavelength" patches?
Have you ever stood above a river or lake and noticed that the surface has visible "patches"? It looks like the surface has different average wavelengths in some areas, leading to the light ...
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Hysteresis in volume of liquids and solids vs temperature
We were asked as a lab experiment to measure the volume occupied by water and ethyleneglicol as a function of its temperature by having a flask inside a body of water at the desired temperature. Then, ...
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Do high powered lasers refract differently than other light?
So I have a question: I am told that there are naval lasers that target over 100's of miles ship-to-ship (not ship to air). Someone asserted that powerful lasers would refract differently than light. ...
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Why does water warm gradually when a faucet is opened?
When you turn on a hot water tap after some idle period, you first get the cooler water that's been in the pipe, then gradually it warms up to the tank temperature.
I've wondered why the warmup is ...
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Would seawater flow be affected by a magnet?
Let's suppose that there are two streams of sea water, flowing on a flat inclined surface. Both of the streams are distant, independent of each other and parallel to each other.
Now lets image I put a ...
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Why does curvature reduce the inward attractive force of molecules?
This question concerns the first 2 paragraphs of this text.
I am struggling to visualize why molecules on the flat surface experience more net inward force than those on a curved surface. If we have 2 ...
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Converting starting wave to known max wave height
in our university project, we are developing a tsunami simulation using the Shallow Water Equations. For our project, we have decided to allow users to enter an epicentre and the magnitude of an ...
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Measuring Temperature of Water-filled Methacrylate Capsule: Laser Thermometer Accuracy and Penetration Depth Inquiry
Imagine that I have a methacrylate capsule filled with water (8cm in diameter and 30cm in length). If I wanted to measure the temperature with a laser thermometer pointing at the capsule, what ...
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Effect of impurities on boiling and freezing points
When impurities like salt is added to water, the boiling point of water increases because of what I think is vapour pressure, though I know very little about that too. However, with the same analogy, ...
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What's the fastest speed water from a glacial dam burst could achieve? [duplicate]
I've been watching a lot of Graham Hancock videos of late, thrusting myself deep into the rabbit hole of pseudoarchaeology/alternative archaeology, and I don't really know enough to assess the ...
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Can water at absolute zero still be liquid?
We see this interesting phenomenon with water bottles in cold chillers left undisturbed for a long time; the water within remains a liquid, but a small kinetic shock, such as a tap, shake or pour, ...
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Does air gap between enclosed chamber and manometer influence the manometer reading?
We have an enclosed chamber filled with water. From the top of the chamber there is a metallic tube connecting the chamber to a monometer. We increase the pressure of the water inside the chamber buy ...
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Why isn’t $\rm H_2 O$ a primordial element? [closed]
We’re told the universe was very hot and energetic immediately after the Big Bang, and just shows H2O was present early on. Yet, it is not considered to be a primordial element. Why is that?, and what ...
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Could one perform a test to determine whether water was warmed by a microwave rather than over a flame?
If I warmed two cups of water from 20 °C to 90 °C, one in a microwave and one over a flame. Is there a test that could be performed to determine how each cup was warmed? Are there residual effects ...
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Any method for measuring hydroxyl and hydroperoxyl radicals in water?
I am looking to irradiate water containing some amounts of iron and would like to measure the amount of hydroperoxyl and hydroxyl radicals produced in real time as a result of the irradiation. Is ...
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Enthalpy of formation function of temperature
Why is the enthalpy of formation a function of the temperature?
We can see in the dedicated tables (such as JANAF),
that the enthalpy of formation changes with temperature.
Doesn't the enthalpy of ...
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Why do hot water droplets persist in cooler water?
I notice this phenomenon typically when mixing hot or warm water with cold water. Basically, tiny droplets of hot water travel inside the body of cooler water and persist. I have included a photo of ...
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