All Questions
Tagged with newtonian-gravity thermodynamics
10
questions
48
votes
9
answers
21k
views
Why is air not sucked off the Earth?
People said outside earth is a vacuum. But the air does not get sucked from the Earth's surface. Some said it is due to gravity and some said the speed of air molecules are not high enough to escape....
- 609
14
votes
6
answers
10k
views
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 ...
- 477
56
votes
3
answers
15k
views
How does the Earth's center produce heat?
In my understanding, the center of the Earth is hot because of the weight of the its own matter being crushed in on itself because of gravity. We can use water to collect this heat from the Earth and ...
- 682
32
votes
11
answers
5k
views
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
15
votes
3
answers
3k
views
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
8
votes
3
answers
584
views
Entropy and gravitational attraction
Any process which is spontaneous and irreversible must involve a (positive) change in entropy of the universe
This is one condition to the spontaneity of a process that the overall universe (System + ...
- 1,059
5
votes
1
answer
202
views
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
2
votes
2
answers
545
views
Energy of room. Ideal gas law
I have been following Blundel's "Concepts of thermal Physics" and I got to the derivation of the ideal gas law. And it all made sense, we made a couple of assumptions and approximations, but then I ...
- 637
0
votes
3
answers
2k
views
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
0
votes
1
answer
4k
views
Vertical surface would lose heat faster by convection than a horizontal surface?
Is the heat coeff affected by gravity?
Vertical surface would lose heat faster by convection than a horizontal surface?
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