What is Equilibrium: Definition and 1000 Discussions
Thermodynamic equilibrium is an axiomatic concept of thermodynamics. It is an internal state of a single thermodynamic system, or a relation between several thermodynamic systems connected by more or less permeable or impermeable walls. In thermodynamic equilibrium there are no net macroscopic flows of matter or of energy, either within a system or between systems.
In a system that is in its own state of internal thermodynamic equilibrium, no macroscopic change occurs.
Systems in mutual thermodynamic equilibrium are simultaneously in mutual thermal, mechanical, chemical, and radiative equilibria. Systems can be in one kind of mutual equilibrium, though not in others. In thermodynamic equilibrium, all kinds of equilibrium hold at once and indefinitely, until disturbed by a thermodynamic operation. In a macroscopic equilibrium, perfectly or almost perfectly balanced microscopic exchanges occur; this is the physical explanation of the notion of macroscopic equilibrium.
A thermodynamic system in a state of internal thermodynamic equilibrium has a spatially uniform temperature. Its intensive properties, other than temperature, may be driven to spatial inhomogeneity by an unchanging long-range force field imposed on it by its surroundings.
In systems that are at a state of non-equilibrium there are, by contrast, net flows of matter or energy. If such changes can be triggered to occur in a system in which they are not already occurring, the system is said to be in a meta-stable equilibrium.
Though not a widely named "law," it is an axiom of thermodynamics that there exist states of thermodynamic equilibrium. The second law of thermodynamics states that when a body of material starts from an equilibrium state, in which, portions of it are held at different states by more or less permeable or impermeable partitions, and a thermodynamic operation removes or makes the partitions more permeable and it is isolated, then it spontaneously reaches its own, new state of internal thermodynamic equilibrium, and this is accompanied by an increase in the sum of the entropies of the portions.
Hi everyone, I need help with this exercise becouse I don't know how to calculate the equilibrium points of a circuit. The original exersice is the following:
Assume that the open loop dynamic response of the OVA-opamp gets captured by Fig. 1(a) and
consider the circuit of Fig. 1(b).
Consider...
Hi, I’m wondering if someone can help me understand this question. I can find a resultant force/vector when given an initial angle but I’m stuck here when the only information is the two magnitudes. I think I’m solving for the unknowns but a little lost on how or what equation I should be using...
Help, this one is completely different, the weird pulley is making it hard for me and I don't even know what to do with it and where to start. The answer is 185N but I want to know how.
so i was wondering what assumptions needed to make this solvable and ' support at both thrust collars can totally support the moments of 400 Nm before they slip' means which axis of moment
I seem completely lost at this. I barely know where to begin. I know that the forces will sum to 0 but the vectoral nature of the question is really confusing me. Best I have is that the distance between e and q2 has to be sqrt(2) times the distance between e and q1. I don't know where to go...
The principal equilibrium in a solution of NaHCO3 is
HCO3-(aq) + HCO3-(aq) <-> H2CO3(aq) + CO32-(aq)
Calculate the value of the equilibrium constant for this reaction.
My solution:
This overall reaction is the same as the sum of the following reactions:
HCO3-(aq) <-> H2CO3(aq) + OH-(aq)...
t is Torque
I is the inertia moment
P is the power
c is the constant light speed
r is the spot distance to the fiber
p is the torsional constant
theta is what we want
In the equilibrium $$t = 0$$
$$ F\Delta T = \frac{E}{c} = \frac{P\Delta T}{c} => *F* = \frac{P}{c} (1) $$
This will be the...
Hello everyone,
For this equation, I have found Ay as 0.677kN by using Ma = 1.5kN(7m)-Ay(15.5m).
To find Cy, would I be using the sum of forces to find the answer?
For example Fy = Ay - F2 - F1sin55 + Cy = 0
This would then get Cy answer as 2.05kN
The boom is supported by a ball-and-socket joint at AA and a guy wire at BB
Hey guys, I am stuck with this question in find the Tension in B and the moments around A. I have done plenty of 2d Tension questions but not a 3D one.
I know what K does, what can change K, and I know about the equilibrium equation. I don't know how to use that to answer this problem. I'm not given any chemical reactions or their K values. How should I start this problem?
When I use the concept of activity to express the equilibrium constant expression, for either equilibrium pressures or concentrations, the units cancel and the value of K has no units (which is how K is customarily reported). But because of the difference in reference states (the reference...
Hi all
Knowing that ##kp## is:
##k_p=\frac{pO_2.(pNO)^2}{(pNO_2)^2}##
And knowing these relationships between the partial pressures, I obtained:
At 700 K:
##pNO = 0.872.pNO2##
##k_p=pO_2.(0.872)^2##
At 800 K:
##pNO = 2.5.pNO2##
##k_p=pO_2.(2.5)^2##
Furthermore it is known that ##pNO + pNO +...
Suppose you have a container of water at a given temperature T (say normal room temperature) with a vacuum above it. Presumably water will evaporate until there is sufficient vapor that the pressure of it above the water is the SVP for that temperature.
Now suppose that there is air above the...
Summary:: I need some help with moment when using equations of equilibrium
Edit: Sorry I forgot to say what the question was! The question was to solve the value of R based on the diagram below alone.
I was solving the question below and I tried to resolve R into a force that is perpendicular...
I have two questions regarding this problem
1. The following is my attempt to solve Fcy using the fact that the addition of torque = 0. I considered force mg and Fcy and their lever arms to set up the equilibrium. But this method seems not to work? Why?
2.At the bottom of the question, it...
Suppose you have a non-uniformly doped piece of semiconductor (without an applied bias) such that the acceptor dopant concentration Na(x) decreases from left to right (as x increases). In this case, the equilibrium hole distribution p(x) will not be uniform since then there would be a net drift...
$$Q_{(\alpha, \beta)} = \sum_{N=0}^{\infty} e^{\alpha N} Z_{N}(\alpha, \beta) \hspace{1cm} (3.127)$$
Where ##Q## is the grand partition function, ##Z_N## is the canonical partition function and:
$$\beta = \frac{1}{kT} \hspace{1cm} \alpha = \frac{\mu}{kT} \hspace{1cm} (3.128)$$
In the case of an...
"The displacements of the blocks
from equilibrium are both measured to the right. Block 1 has a mass of 15 grams and block 2 a mass of 10 grams. The spring constants of the springs are shown in dynes/cm."
I don't know if i understood very well the notation, but i interpreted as F(t) acting only...
It is desired to remove the molecular hydrogen present in a flask. What will be better to introduce, ##Cl_2## or ##Br_2##? Why?
##2 HCl <-> H_2 + Cl_2## (1)
##k = 3,2.10^{-14}##
##H_2 + Br_2 <->2 HBr## (2)
##k = 2.10^9##
I thought about turning equation (1) to make the...
My initial response to seeing the figure is what is ##F_{ua}## and where does it come from? How was i supposed to know it was there is they didn't give a picture?
So for part a, ##F_{ua}## doesn't play a role because it exerts no torque, and apparently we are supposed to use the torque equation...
According to the book "Principles of Statistical Mechanics" by Amnon Katz, page 123, ##\alpha## must be such that ##\exp ( -\alpha N ) ## can be expanded in powers of ##\alpha## with only the first order term kept. Is this the necessary and sufficient condition for small deviations from...
When a ball is thrown upward it becomes at rest at maximum height, at this it is not in equilibrium although it is at rest. It is not at equilibrium because force of gravity is acting on it? Still I cannot find good explanation from exam point of view.I also cannot find the figure/diagram.
I know the acceleration of the rock is equal to g, but why. If we neglect air resistance, what is actually making the rock fall? Wouldn't it be that g overcomes the acceleration of the y plane at some point so the rock starts coming down or in this case accelerate more by throwing below 0 degrees?
So I have always been thinking that equilibrium means that an object is not moving or having constant acceleration. On a webside they said: " A rigid body is in equilibrium when it is not undergoing a change in rotational or translational motion. " To me it sounds like the object then must not...
So here are two problems I have been working with lately:
I have solved both, so I don't need the help to find the answers. The thing that confusses me is which object one should choose to apply the equations above. When it comes to the first problem, we apply the equations to the pole, but...
A diagram of the physical situation is below:
Choosing the positive ##y## direction to be upwards and the positive direction of rotation to be counterclockwise, Newton's linear second law gives:
$$-m_D g + F_L + F_R = 0$$
where ##F_L## is the magnitude of the force exerted on the bar by the...
Abs Pressure:
Gauge press: 1 bar G = 100,000 Pa = 0.987 atm
0.1 bar G = 0.0987 atm
Atm press = 101.3 kPa = 1 atm
Hydrostatic press: average CO2 occurs 2.5m up the vessel
(9.81 ms-2)(1010kgm-3)(5/2) = 24,770.25 Pa
1 Pa = 9.869x10^-6 atm
24,770.25 Pa = 0.2445 atm
Abs press= 0.0987 atm + 1 atm...
The diagonal component of the boom's weight is ##R=w\cos\frac{\pi}{6}=\frac{\sqrt 3}{2}w##, and, considering ##R## as a "reaction", we have ##R_x=R\cos\frac{\pi}{3}=\frac{\sqrt 3}{4}w## and ##R_y=R\sin\frac{\pi}{3}=\frac 34w##.
I will also have...
I don't understand the question; they're telling me that the fulcrum is just under the center of gravity of the bar, but that I also need to find its position.
In any case, I suppose that the fulcrum's position is ##x##.
Let the weight at the left end be ##w_1##, at the right end be ##w_2##...
I take the left end as reference for torques:
$$\sum\tau=F_\text{support}+\frac 32\times280+3\times500=0\Leftrightarrow F_\text{support}=-192.\times10^1\,N$$
It's facing up.
I take the right end as reference for torques:
$$\sum\tau=-192.\times10^1\times2+\frac 32\times280+3F=0\Leftrightarrow...
I'm wondering if I'm on the right track and if anyone is willing to steer me on if not:
Equilibrium vapor pressure (EVP—also referred to as saturation vapor pressure) is dependent only on temperature. Outside pressure has no bearing.
Now, of course, with lower external pressure (atmospheric)...
Here is one scenario:
I have placed a metal in my room which is at room temperature. Air has little much heat capacity and metals don't like to store heat. Would heat transfer occur? Whatif I set the temperature of both to a certain degree where it crosses heat capacity of metal but not of air?
(figure)I was able to solve the problem and get the right answer. However, I solved it more with intuition, and I do not get how the force of the person pulling down on the rope makes the force to the left of the backpack equal to force to the right of the backpack.
Equal masses of ice at –10ºC and water at 80ºC are placed in an insulated container and allowed to reach thermal equilibrium. Calculate the equilibrium temperature
Data:
Water(ice): 37,65 J/mol.K Agua (l): 75,29 J/mol.K
## Lf = 6011 J/mol ##
I solved it this way:
## -Q_{l} = Q_{ice} ##
##...
I honestly have no idea where I'm going wrong
i've checked my differentiation using a derivative calculator but the answer is the same.
The answer from the book is \frac{L}{2} + \frac{h^2}{L}
Working:
I set the electrostatic force exerted by the object at (0,0) and (3,0) equal to each other, dividing out k and q2. I was left with q1/d^2 for both terms and substituted in the given charges for each object. I then replaced d^2 for the object at (0,0) with “x^2” and d^2 for the object at (3,0)...
These are the images from Sommerfeld’s Lectures on Theoretical Physics, Vol 2 chapter 2, section 6, Equilibrium of Incompressible Fluids.
Image 1
Image 2
Doubt 1 : What does it mean for a force to act on a fluid volume? Force acts on a point, force may act on a surface but I’m unable to...
Absolute pressure is gauge pressure + atmos press
Guage press = 1.29 bar G
1 bar = 10^5 Pa
1.29 bar = 129,000 Pa
Atmos Pres = 1.01x10^5 Pa
Absolute pressure = 230,000 Pa
Henrys law: P=KhC
230000Pa = (116x10^3Pa)C
1.98 mole fraction =C
70% CO2 = 1.387 mole fraction
44g Co2 in 1 mole
61.07g...
First I found partition functions of both the systems and hence total energies of them using above formulas.
Z(A) = (1 - e-ε/kT)-1 and Z(B) = (1 + e-ε/kT)
Then I equated these values to the given values of total energies.
I got:
For System A, T(A) = ε/kln(2) > 0
For System B, T(B) =...
Absolute pressure = Gauge press + Atmos press
Atmos press = 105 Pa
Co2 press = 0.1 bar g = 10000Pa
Abs press = 10,105 Pa
Hydrostatic pressure = absolute press + (density)(grav)(height at midpoint)
= 10,105 + (1008)(9.81)(10)
10,8989.8 Pa
Calc CO2 conc by henrys law
P=KHC
C=P/KH
=...