All Questions
Tagged with classical-mechanics thermodynamics
193
questions
4
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2
answers
235
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Phenomological vs empirical
"Thermodynamics is a phenomenological theory"
I am not able to understand the difference between empirical and phenomenological descriptions, aren't all theories empirical?? Do we say some ...
- 592
0
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2
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86
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Why is mechanical work equal to Joule heating?
This question came about when I was doing a problem related to a conducting loop with resistance $R$ moving with velocity $v$ in a magnetic field. It asks you to verify an expression for the force ...
- 234
1
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0
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60
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Does the Legendre transformation describe two views on the same physical system or different physical systems?
In mechanics we perform the Legendre transform to go from the Lagrangian $L(q, \dot{q})$ to the Hamiltonian $H(q, p)$. This seems to be describing the same physical system. $L$ and $H$ both describe ...
- 131
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15
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How to calculate the surface heating of the ball thrown in different fluid mediums like air and water?
Let's say a ball is thrown at a certain velocity, then it follows a projectile motion and falls on the surface. Now, during this entire flight how can we calculate the temperature rise that happens in ...
- 101
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2
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Very briefly, what is the relation/difference between classical field theory and classical thermodynamics/statistical mechanics?
This is probably not a good question, since I am at a fairly low level, but I am a little bit confused when the two concepts were described to me and it's bringing discomfort during my study.
What I ...
- 243
4
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63
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How negligible is a term in the internal energy for the equipartion theorem in classical mechanics?
The equipartition theorem is a well-known result of classical statistical mechanics, and it states that if the Hamiltonian of a system can be written like this:
$$H=\sum_{j=1}^m {\alpha_j\ {x_j}^2}$$
...
- 41
0
votes
1
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73
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How fast do particles travel in space? [closed]
Does the speed of the particle in space depend on its mass? For example, if the objects are subjected to same energetic phenomena like supernova, do the heavy objects move slower than lightweight ...
- 425
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votes
1
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75
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Help regarding discovery question in Thermodynamics
new to the forum and I'm currently learning about "heat capacity" in my physics book, and I've had a bit of a tough time trying to see the reasoning behind a certain question. In this book, ...
- 49
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0
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60
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What happens when you heat 5 cubic meters of iron to 3500k in 0.1 seconds?
I've been googling this problem all night. I have no relevant degrees in physics, but I'm fascinated by it.
In the Warhammer 40.000 universe there is a portable weapon called a "melta" it is ...
0
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2
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78
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Is this set up a reversible process and is the adiabatic equation of state applicable here?
I had this question in a recent test:
My teacher while discussing this question used the adiabatic equation of state PV^gamma=constant to solve for length L (options C and D). And used work energy ...
- 105
2
votes
1
answer
210
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Conflict between a system lowering its potential energy and kinetic energy
Every system in the universe has a natural tendency to attain a state of minimum energy. The state of minimum energy corresponds to a state of maximum stability.
These are from a renowned book. I am ...
- 312
1
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1
answer
75
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In mechanics ($\mathrm dV/\mathrm dx = 0$) in equilibrium, what about thermodynamics?
In mechanics we say that net force acting on a system is zero ($\mathrm dV/\mathrm dx = 0$) in equilibrium. In a similar way, which quantity should remain constant in thermodynamics?
- 457
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2
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304
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Why should layers of air rise up and the layer above it takes it place
I am a high school student and I am very confused in a topic dealing with "why hot air rises up" I know it is already answered but the answers are difficult for me to understand I want a ...
0
votes
0
answers
42
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Details on why temperature is lower at high altitude
I have read at so many places that warmer air moves up as hotter substances expands and as it rises it loses its kinetic energy and it gets converted into its potential energy(gravitational+...
0
votes
1
answer
206
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What do these straight lines in the graph mean?
Does it mean thermal equilibrium? If the answer is yes, then how do we get to the molecular dissociation stage when we have already reached thermal equilibrium in vibrational mode?
Because equilibrium ...
- 47