1,288 reputation
519
bio website
location
age
visits member for 2 years, 10 months
seen 10 mins ago

Dec
5
awarded  Constituent
Dec
5
comment Why are Navier-Stokes equations needed?
"Theoretically, we can show that in the hydrodynamic ..." I believe this paragraph is wrong at the current time. I thought you can derive NS from the Boltzmann equation, so techinically you can derive NS to a certain extent only for gases, but not for liquids. Or do you know statistical NS derivation for liquids?
Nov
27
answered Speed of Entropy change
Nov
27
awarded  Caucus
Nov
27
comment Is it possible to have a Gas heavier than a liquid?
@MartinBeckett I thought of this, but such materials would be better qualified as foams, not as liquids. I was looking for the lightest paraffin, but they are still quite heavy.
Nov
26
comment Is it possible to have a Gas heavier than a liquid?
Maybe there is some really light "solid" material which is a supercooled liquid, like glass but much more lighter. Of course you won't get a thermodynamically equllibrium state, but mechanical equllibrium might be possible.
Nov
9
accepted Is it wrong to talk about wave functions of macroscopic bodies?
Nov
9
comment Is it wrong to talk about wave functions of macroscopic bodies?
Where exactly is that information in the article?
Sep
18
revised How slow is a reversible adiabatic expansion of an ideal gas?
added 400 characters in body
Sep
18
comment How slow is a reversible adiabatic expansion of an ideal gas?
Do you mean there is no entropy production outside the the kinetics scale?
Sep
18
answered How slow is a reversible adiabatic expansion of an ideal gas?
Sep
18
answered Waves travelling with water flow
Sep
17
comment How many years will the nuclear resources of Earth last for generating electricity?
Tom Murphy's analysis might be of interest physics.ucsd.edu/do-the-math/2012/01/nuclear-options
Sep
14
comment Is it possible that nuclear fission contributes to climate change?
@CatherineHoy for some strange reason they contrast mass and energy, but roughly if you have one you have the other. Probably en.wikipedia.org/wiki/Mass%E2%80%93energy_equivalence will clarify. In nuclear fission one atom splits in two, the two combined are lighter then the original atom. The mass difference is the energy you gain $\Delta m c^2$.
Sep
14
comment Is it possible that nuclear fission contributes to climate change?
@CatherineHoy "However, this law does not apply to nuclear energy because it is produced when atoms of matter are split or fused." The law of energy conservation perfectly holds for nuclear reactions. Why do you think the opposite?
Sep
14
comment Collision between Neutron stars and Black holes
"Why is the difference between all these collisions" What "these"? What are the possible collisions you are considering?
Sep
14
comment Work on ideal gas by piston
@mythealias second viscosity for normal gases is zero, no dissipation will have place, except for the boundary layer at walls. That's just like sounds, I bet you know the derivation of the sound speed in gases, the process is rapid, but you use equilibrium relations and assume no dissipation. Of course if the piston is not so rapid to cause shock waves.
Sep
14
comment What is the maximum surface charge density of aluminum?
oops, I meant $\sqrt{e / \sigma}$ Your sigma is in SI (Coulombs /m ^ 2) ?
Sep
14
comment What is the maximum surface charge density of aluminum?
@thrusty I think as you've expected $\sqrt{\sigma / e}$
Sep
13
revised What are some molecules stable in outer space that are unstable under terrestrial conditions?
edited tags