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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Is there any formula to calculate the impact when falling onto water surface from speed?
So I know how to do the math of instantaneous speed when doing free fall:
$$v = g \cdot t $$
and here comes into my question: how can I calculate the impact on water surface when hitting it at a ...
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Is the strongest acoustic signal always the closest?
I have a single beam echosounder that I use to measure the distance to an object underwater. It emits an acoustic pulse and listens to the reflections. Using the time of flight and the strongest ...
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Froze or freeze bottle Exploding
I kept a bottle in my freezer with full water overnight. When my mom took it out and put it in normal condition, it blasted after a few minutes. More surprisingly the bottle was made of aluminum. Pls, ...
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Is light penetration through water affected by water pressure?
Does water pressure affect propagation of light through water?
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Why does pouring water have a slightly different color when viewed from above?
I have noticed when I view a hose pouring water the color of water slightly changes when looking from above compared to when looking from the front.
Also, the same thing applies when you pour water ...
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Why does boiling water in the cold instantly evaporate if it is splashed out of a mug?
If I pour boiling water into a mug and throw it out from the balcony in very cold weather (-20 degrees Celsius and below), then it instantly turns into a cloud of steam, even before it reaches the ...
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How to find the rate at which water can pass through a semipermeable membrane that allows particles of size lesser than 0.5 mm?
I was wondering what would be the rate at which water would cross a semipermeable membrane that allows particles of size greater than 0.5 mm. Knowing that size of water molecules is 2.75 angstroms ...
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What is the difference between the specific heat capacities of water under isobaric and isochoric conditions?
Can the difference of specific heat capacity of water under isochoric and isobaric conditions be explained in terms of the internal energy of the system? Most of the videos I have watched base their ...
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Is the triple point of water exactly 0.01 $\deg$C?
Is the triple point of water exactly $0.01 \deg$C, or is this an empirical value/is there some uncertainty to it? If so, how do we know it is exact, and why?
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Melting point of water [duplicate]
Wikipedia says about melting point that:
The melting point of ice at 1 atmosphere of pressure is very close to 0 °C (32 °F; 273 K); this is also known as the ice point.
But why it is very close and ...
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The solubility of gases in liquids. Laws and equation [closed]
I am studying the solubility of gases in liquids (flowing then into the study of oscillations of gas bubbles out of the liquid phase).
The task at the moment is to familiarize myself with the laws of ...
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How much can water be compressed?
How much can liquid water be compressed?
I mean the maximum achieved in practice and the maximum achievable in theory.
Say for example one liter of water at 4 degrees Celsius.
Can it be compressed to ...
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What's the most practical method to calculate Complex Dielectric Constant of Water?
I need to find the real part and imaginary part of Complex Dielectric Constant of Water, in calculation of ITU P.618-9 rain attenuation model. In my calculation using the model, the carrier frequency ...
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How does wetting cotton increase its UV transparency?
Anecdotally, a dry cotton T-shirt prevents sunburn better than a wet one.
This has also been measured (Gambichler et al., "Influence of wetness on the ultraviolet protection factor (UPF) of ...
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What effect does salt have on the boiling speed of water?
My question is the following:
I have two pots. Pot A and pot B. I fill both of them with 1l (litre) of water. Now I add a table spoon of salt into pot A. Which water is going to start boiling first?
I ...
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Electricity through water
If you're sat in a body of water through with an electric current runs, can you survive if you create an earth wire to lead the electricity away from you?
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Can capilliary action move liquid against gravity?
I was wondering if it was at all possible to very slowly suck up water from a cup with a rope, and then deposit the water into another cup on a 3cm thick book or similar object.
Here is an example ...
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How carbon water filter can build air pressure inside (before installation)? [closed]
Today I got a new refrigerator carbon water filter. Before installing, out of curiosity, I dripped a bit water into the filter’s outlet to see if water could flow in and out. Obviously it did… Then, ...
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Is there a temperature at which ice is denser than water?
Normally ice would float on water because its density is less compared to that of water as a liquid.
But is it possible that its density will increase due to a very low temperature or is ice in any ...
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Can heavy water be isolated with water centrifuges?
If a container of pure water is rotated fast enough at high rpm, would $\mathrm{D_2 O}$ separation be feasible?
Another way to ask is: it practically and physically possible with current technology ...
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Why does wind blowing across a bird bath cause the water to freeze even though the ambient air temp is 39 - 40 degrees F?
Frequently, after cold frontal passage, a strong NW wind blows across the open marsh and through our back yard. With ambient temps still well above freezing, the surface of the water in our concrete ...
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Using the electrolysis of water to cool a room [closed]
Browsing the internet today I came across this very esoteric paper which purports to describe the construction of a device which uses the electrolysis of water into hydrogen and oxygen (a highly ...
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Water traveling on a letter in a water feature
Difficult for me to ask as I'm not a physicist.
Assume you have a water feature in the form of a waterfall where the water runs down a wall. On this wall, there are letters attached by a raised ...
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Compressed water
Normally, water is incompressible, but what happens if I have a fixed volume and keep pumping water into it?
Let's say I have a compartment full of water. The compartment is completely sealed off, ...
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Why does water turn into water vapor?
I read an article lately and it said that water turns into steam when it reaches its boiling point. But it led me to another question.
Why does water boil and why does the water turn into gas when it ...
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Water molecule formed by at least one tritium atom
If a water molecule is made up of at least one tritium atom, when the tritium atom(s) decay radioactively, what happens to that water molecule? Does it bond to one or two Helium atoms? Is there any ...
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Is it possible to make large waves from perfectly timed single drops of water?
Assume I have a hemispherical container of water and an eyedropper. Is it possible to add water to the container one drop at a time, such that each drop continues to add kinetic energy to the water?
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Why does a narrow line of falling water seem drop drop when quickly looking at it from top to the bottom?
When I was under the shower I experienced when I look quickly at a single line of water falling from one pore (from top to the bottom) it looks "drop drop" instead of continuous. Why is it ...
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Physics model for my tub of water demo
I want to setup a demo to show people an intuitive example of causal inference (Pearl 2009) using a simple experiment.
I have a tub of water with two accelerometers floating on the surface. In the ...
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Changes in Water Bonding Angle
I heard something recently in a casual discussion, but have yet to be able to confirm it: is there any evidence that the bonding angle for a water molecule, currently defined as 104.5, has been either ...
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Breaking apart the surface tension of a water droplet
How far apart do two vertical glass surfaces have to stand for a water droplet that is sticking to both of them to break into two?
I apologize in advance for the question possibly being too imprecise �...
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Hydrostatic pressure to measure water level
I am measuring water level in a 25-inch tall vase using hydrostatic pressure. Like this.
To do this I have a 1/4 OD inch nylon tube connected to a gauge pressure transducer. So far it has been very ...
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Gravity vs adhesion of a water droplet
How much volume can a water droplet that is attached to a vertical glass surface have before it begins to roll downwards?
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Salt water and ice, vs. plain water and ice
A famous puzzle is whether an ice cube melts to nothing more quickly in salt water or fresh water. The answer is fresh water, because the water melting off the ice cube sinks in the plain water and ...
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Why does the water go from left to right in this question?
In this problem stated by Brilliant course in "Flow in pipes", the water flows from left to right without explaining anything:
My doubt is if I'm supposed to assume there is some greater ...
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Underwater chests in video games
Many video games creators put chests with items in various places. Sometimes the chests can be found underwater. Here are two examples:
Dying Light 2
Shadow of the Tomb Raider
However, I started ...
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Water as heat source in a heat pump
Consider we have water flowing in a pipe, which is working as a hot source for a heat pump. We are able to know the temperature of the water in both ends of the pipe, yet we don't have information ...
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How much $\rm CO_2$ can you save by overfilling a SodaStream bottle? [closed]
For people who don't know what Sodastream is: SodaStream is a system where you can make your own soda at home using regular water and a CO2 cartridge. You put water in the special Sodastream bottle, ...
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Water in vacuum (or space) and temperature in space
So, water in vacuum will boil first and then freeze. I don't know how the freeze happens. As pressure lowers to zero, what happened to freezing point? (I know heat taken by vapor, and the water cool ...
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Why does the water not flow on this tub [closed]
I found this problem on Brilliant and it's quite interesting because you have 2 tubes that are connected and on both ends they are put under a different pressure:
On the upper hole there is less ...
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Why does water come out of a bottle in waves?
So imagine you have a bottle of water or any type of liquid (like a bottle of milk that has just been opened)that is completely full or even three quarter of it is full,why does the water or milk come ...
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Why are there 2 ways of predicting if an object will float or not?
I thought about it for a second, I have always thought that for an object to float it had to be less dense than water, and if it had more density then it would sink. But then if it sinks or floats ...
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How do you calculate the power needed to pump water with a hand water pump?
I have a doubt about the way in which I could calculate the power requiered to pump water with a hand water pump like the next one:
I´ve seen that many people use the equation below:
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Why if I raise my hand over the water while being underwater, my whole body goes down?
Another weird question, I know, and may sound simple but I'm now trying to see why a lot of the things that we usually do without thinking, have some sense in physics, like this one.
Let's say you are ...
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What is that makes us slow down in water? [closed]
I know this may sound very weird, but I'm curious on what makes the water be like water? Like why, when we get into a pool, we are like in a "lower gravity" pull? All our movements are ...
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How has Earth's atmospheric water been in previous eras and periods?
How has partial pressure and net amount of water vapor and colloidal water been in previous eras and periods on Earth?
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Does boiling a cup of water from room temp take the same amount of time as having a pot of boiling water and putting a cup of room temp water in it?
I was thinking and had this discussion with my sister about this. I said that if I had the same stove and same pot and whatever that boiling 1 cup of water in an empty pot would take the same amount ...
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Increase water pressure (e.g. for watering the garden) using the principle of a hydraulic press
Does anyone know a device that incorporates this principle? Process is as follows:
You get a lot of water at low to mid pressure (let's say 1 bar)
A device D converts the work that 1 liter of water ...
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Why does water cast a shadow even though it is considered 'transparent'?
If you pour water from a container, the flowing water stream seems to cast a shadow. I am not sure you can call it a shadow, but it definitely is not letting all light through it. How is this possible ...
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Will just the increase in height of water column increase pressure or does mass play any role in it?
As we know pressure exerted by any liquid at any given point in a container can be calculated by the formula $P = \rho g h$. Product of density of fluid, acceleration due to gravity and the depth from ...
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