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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How does water evaporate if it doesn't boil?
When the sun is out after a rain, I can see what appears to be steam rising off a wooden bridge nearby. I'm pretty sure this is water turning into a gas.
However, I thought water had to reach 100 ...
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What is the status of Mpemba effect investigations?
There is this puzzling thing that is called Mpemba effect: paradoxically, warm (35°C) water freezes faster than cold (5°C) water. As a physisist, I've been asked about it several times already. And I ...
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How to show that the Coriolis effect is irrelevant for the whirl/vortex in the sink/bathtub?
There is a common myth that water flowing out from a sink should rotate in direction governed by on which hemisphere we are; this is shown false in many household experiments, but how to show it ...
user68
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Patterns in laminar flow of tap water
This is a simple experiment that anyone can do at home. Open your tap so that the water maintains a laminar flow, and the cross section of flow is considerably thin. Place your finger 3-4 cm below the ...
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How to find out the maximum radius of a hole that can keep water stay in a container by water viscosity?
Assume I have a inverse cone which holds 200ml water. I am going to cut the tip of the cone to create a small hole. How to calculate the maximum radius of the hole that the water will still stay in ...
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Why does ice melting not change the water level in a container?
I have read the explanation for this in several textbooks, but I am struggling to understand it via Archimedes' principle. If someone can clarify with a diagram or something so I can understand or a ...
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Why does sunset over a body of water cause a path of light stretching towards the horizon?
Have you ever notice the sunset's image in the sea? It's like long light path to the end of the horizon! I've attached a sample of this:
How can we explain this? I know that it can happen even in ...
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Why is boiling water loud, then quiet? [duplicate]
Water in my electric kettle makes the most noise sixty to ninety seconds before the water comes to a full boil. I have been fooled many times by the noisy kettle, only to discover that the water was ...
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Why does blowing on someone who is wet feel colder than on someone who is dry?
The title says it all. If I'm standing in the wind and I'm wet, I feel much
colder than when I'm dry. This is true no matter how warm or cold the water.
Why is this?
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Calculation of pressure from flow rate of water
Anybody kindly help me to find how to calculate pressure in bar from flow rate. I have a pipe and from that I am transferring water at a constant flow rate of 5ml/min. At this flow rate, with a 0.5 cm ...
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Why is jumping into water from high altitude fatal?
If I jump from an airplane straight positioned upright into the ocean, why is it the same as jumping straight on the ground?
Water is a liquid as opposed to the ground, so I would expect that by ...
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Waves in water always circular
I have had a question since childhood. Why do we always get circular waves (ripples) in water even when we throw irregularly shaped object in it?
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How is the water meniscus at the edge of a capillary tube?
Suppose we have a capillary tube in which water can rise to a height of x cm.
If we dip the tube such that the height above the surface is less than x, then how will the water meniscus be at the edge ...
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Why is water clear?
Water appears transparent to visible light, yet most other objects are opaque. Why is that? Is there an explanation why water appears transparent?
Is water transparent at all wavelengths, or are ...
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Why does water pouring from a glass sometimes travel down the side of the glass?
If you have a glass of water, say, three quarters full and you pour it at an angle of say, $45^{\circ}$ with respect to the the table, the water comes out of the glass and goes directly down towards ...
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