All Questions
13
questions
1
vote
0
answers
20
views
Howe energy is exchanged in vortex tubes?
In vortex tubes, energy is transferred from some particles (which will be pushed to the centre (how?) and form the cold stream) to some other particles (peripheral particles, which will form the hot ...
- 1,148
2
votes
1
answer
75
views
Since water can evaporate at any temperature above absolute 0, would the water cycle still be possible even without the Sun?
Since water can evaporate at any temperature (or even sublimate at less than 0°C, although at a very low rate: Why does water not evaporate in below 0 degrees?), could there be a water cycle if there ...
- 2,462
0
votes
1
answer
772
views
Optimisation of pop pop boat?
This beautiful video of Steve Mould explains the working of a pop pop boat using a glass boat.
Now he explains that the pop pop boat doesn't move because of ejecting water in one direction like a ...
- 145
0
votes
1
answer
115
views
Deduction of the entropy balance equation with input and output of matter by convection (mass flow)
In many books of Engineering thermodynamics, the entropy balance equation is wrritten as
$\frac{dS}{dt}=\Pi_S+I_S$
$I_S=\sum_{j=1}\frac{\dot{Q}_{j}}{T_j}+\sum_{i=1}\dot{m}_is_i-\sum_{e=1}\dot{m}_es_e$
...
- 3
1
vote
2
answers
1k
views
Work done by the gas in free expansion
I am a high school student and I am a little confused in a free expansion of gas, My teacher told me that when an ideal gas expands adiabetically against vacuum there is nothing on which the gas does ...
- 470
0
votes
2
answers
39
views
Sunlight-powered device set to change world: will it work? [closed]
Vast areas of desert sand are being shone on upon by the sun. Now that's some ENERGY!
Using this proposed apparatus:
Sunlight over large area is concentrated on steam chamber, where water turns into ...
- 340
0
votes
1
answer
76
views
Importance of fluid mechanics and mechanics in physics and pipes
How does mechanics help prevent the pipes from bursting?
How does it link to the pressure of a pipe?
How does fluid mechanics link to physics when its about the liquid phase of chemical processes?
- 5
0
votes
1
answer
154
views
Is latent heat only released and absorbed as radiation?
Can water simply absord the kinetic energy from colliding air molucules to change its phase?
And can water transformed into ice simply have the kinetic energy of its molecules increased to balance out ...
-1
votes
1
answer
93
views
What is the bulk compressibility of a system that contains both water and steam?
Let's say I have a volume that contains both water and steam, e.g. there is a lower pressure top part that is steam and a higher pressure bottom part that is water (temperature is constant).
If I ...
- 103
0
votes
3
answers
10k
views
Flow through a nozzle
Why the gas temperature and pressure decreases while passing through a nozzle?
I have read that in a nozzle velocity increases at the expanse of pressure drop.But how temperature varies with that? ...
- 47
0
votes
1
answer
1k
views
How would an increase in temperature affect ooblek's (non newtonian fluid) viscosity?
Due to the fact that Ooblek (cornstarch and water), contains so much water and from what I understand it is non newtonian due to the particles suspended in it, would it therefore be correct to say ...
- 11
7
votes
2
answers
606
views
Liquid column "recoils" in a sealed cylinder when hit by a piston -- is it possible?
Consider a cylinder filled partially with a liquid (e.g. water). The cylinder is sealed, and is at held at room temperature (e.g 298K). At equilibrium (or when no external disturbance is imparted to ...
- 211
6
votes
1
answer
197
views
Do vortex tubes work with a reversed end plug?
Would a vortex tube still work if instead of a cone plugged into the 'hot' end you had a smaller hole on the 'cold' end? As I understand it, the point of the cone on the hot end is to only allow the ...
- 161