All Questions
Tagged with newtonian-gravity thermodynamics
43
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Global warming: change in Earth's potential energy
It is quite common to hear in newspapers and television about the increasing temperature, i.e. global warming.
But I am interested in something else.
How does global warming affect the internal ...
- 347
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3
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What is precisely the reason that a helium balloon ascends?
A simple question with no clear answer for me: Helium is lighter than air and lighter air rises. That's it!?
I) A helium atom is approx. 4 times as light as an an air molecule. With 4 times less mass ...
- 3,348
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How does hot air act in zero gravity?
In an environment with gravity, hot air is less dense than cool air, so it rises.
How does hot air interact with cold air in a zero gravity environment, in terms of movement? Does it just stay where ...
- 191
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Does gravity acting on a resting object produce any heat?
Let's compare two systems.
System 1: A box is completely isolated. There are no forces acting on that object, and no interactions of any kind with other objects, waves, etc..
System 2: The same box ...
- 556
12
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2
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Will Neil Armstrong's moon boot marks really last for thousands of years?
This question concerns the residual heat (if any) contained within the Earth's moon.
At the time of the Apollo moon landings, it was widely reported that the boot marks left by the astronauts would ...
user81619
5
votes
1
answer
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For $N$ particles acting under gravity, how long until they settle into a virial equilibrium?
As the title says, if I have a system of particles interacting only due to gravity, over what timescale do we expect them to fall into a virial equilibrium?
By virial equilibrium I mean a system that ...
- 1,751
15
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3
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Which ball falls faster, the cool one or the hot one?
Suppose we're on the top of the Tower of Pisa (or a larger version of it) with two identical cannonballs. We heat one up (say, to 200 degrees Celsius, or some other high temperature before it starts ...
- 6,745
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Heating of two identical balls [closed]
You are given two identical steel balls of radius (say) 5 cm. One ball is resting on a table, the other ball is hanging from a string. Both balls are heated (with a blow torch) until their radii have ...
- 659
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In reverse time, do objects at rest fall upwards?
I want to develop a game where time runs backwards, based on the idea that physical laws are reversible in time. However, when I have objects at rest on the earth, having gravity run backwards would ...
- 422
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How does one calculate where the "surface" of a gas-giant would be?
Okay, so Jupiter, Saturn, et. al are gas giants. I understand that they have large gassy atmospheres, which, due to the pressure would eventually become more and more dense as one approaches the ...
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Does gas spread out equally everywhere?
An excerpt from this page:
Gases can fill a container of any size or shape. It doesn't even matter how big the container is. The molecules still spread out to fill the whole space equally. That is ...
- 1,531
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What keeps a gas giant from falling in on itself?
There is not enough gravity at the center to start nuclear fusion, but it seems that there would be plenty enough to collapse the planet.
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Can low-gravity planets sustain a breathable atmosphere?
If astronauts could deliver a large quantity of breathable air to somewhere with lower gravity, such as Earth's moon, would the air form an atmosphere, or would it float away and disappear? Is there a ...
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