What is Process: Definition and 1000 Discussions

Hi, I have read that for an irreversible process the equation for the entropy is: $$ds>\frac{dQ}{T}$$ But if I regard a cylinder connected to a heatreservoir and want to callculate the entropychange of this cylinder, why can I use the equation: $$ds=\frac{dQ}{T}$$? THX

Homework Statement Hi everyone In an isochoric process ( a solid heat body with T1 temp. connected with heat bath with T2 temp) we could calculate its entropy change(heat body) from dS = Cv/T dT and entropy change of heat bath from dS = dQ / T2, using dQ = Cv dT in 1st equation ( i...

Looking at some German/Swiss masters programs (mainly computational mechanics in Stuttgart, München, Lausanne) but having a tough time figuring out the admission process for international students. Do they generally only look at your bachelor's degree GPA and nothing else or does other stuff...

Homework Statement X_t and Y_t are poisson processes with rates a and b n = 1,2,3...Find the CDF F_X{}_t{}_|{}_X{}_t{}_+{}_Y{}_t{}_={}_n(x)Homework Equations The Attempt at a Solution F_X{}_t{}_|{}_X{}_t{}_+{}_Y{}_t{}_={}_n(x) =P(X_t<x|X_t+Y_t=n) =\frac{P(X_t<x,X_t+Y_t=n)}{P(X_t+Y_t=n)} Not...

E(Xn+1+i)=Ʃn+ij=i+1 cj-iXj, where Ʃnj=1 cj = 1. n is a fixed constant here, c is a fixed set of n coefficients. Can anyone tell me anything about such a process?

Hi, I regard a irreversible cycle process. It is a cylinder filled with gas, which underlies the following processes: 12: isothermal compression (reversible) 23: adiabatic expansion (reversible) 31: isochor heating (irreversible) [This happens by connecting the cylinder with a...

Homework Statement 120 mol/min of Propane (C3H8) is burned in the presence of air (21% O2 and 79% N2) in a furnace, two reactions occur: Complete Combustion: 67%, propane is burned to CO2 and H2O Incomplete Combustion: 18%, propane is burned to CO and H2O Oxygen is supplied at 70%...

For the basis of a report in university, i have been given an assignment which involves discussing various surface treatments. Is galvanizing a surface treatment? Some sources refer to it as a surface coating because obviously it involves building up layers of zinc oxide.

Most of the book using PV=nRT for PV^gamma constant for adiabatic process. However, please refer attachment, proving using conservation of energy will also make sense?

Homework Statement I'm taking a practice test and I need some help with a heat engine problem. There are three parts, the one that's giving me trouble is a-->b. The Volume v. Pressure graph shows a straight line. Pa= 5 atm Va= 5 L Ta=300K and Tb=800K are given. So pressure is decreaseing...

I have a query on a Random process derived from Markov process. I have stuck in this problem for more than 2 weeks. Let r(t) be a finite-state Markov jump process described by \begin{alignat*}{1} \lim_{dt\rightarrow 0}\frac{Pr\{r(t+dt)=j/r(t)=i\}}{dt} & =q_{ij} \end{alignat*} when i \ne...

Hi all. I'm trying to become acquainted with thermal dynamics. I thought I had a fairly good handle on the idea gas law, PV=nRT, or PV=mRT, but I came across a problem involving the throttling of an idea gas, and the solution was totally not what I expected. Referring to picture where gas...

I want to know what catalyst is used in the Fischer–Tropsch process to get fuels.

Homework Statement given that ∫01 xndx = 1/ n+1 for integers n \geq 0 calculate these integrals Homework Equations ∫01 (1+x+x2) dx The Attempt at a Solution I have found the definite integral of ∫01 (1+x+x2) dx to = 1.8333... (ie. 11/6) but all I did was use my TI-84 to find...

Homework Statement Consider a one-way road where the cars form a PP(lambda) with rate lambda cars/sec. The road is x feet wide. A pedestrian, who walks at a speed of u feet/sec, will cross the road if and only if she is certain that no cars will cross the pedestrian crossing while she is on...

In a rolling process, the state of stress of the material undergoing deformation is a) pure compression b) pure shear c) compression and shear d) tension and shear Which one is the correct option ? Please explain why !

http://www.foxnews.com/science/2013/02/20/coal-cleanest-energy-source-there-is/?intcmp=HPBucket#ixzz2LUZ8Z69v I'm not seeing it. The problem is obvious: The primary combustion products of coal are water and carbon dioxide. The proportions vary with the type of coal, but a considerable...

Hello all, Considering that Einstein told us that E=mc2, that means that any energy is generated at a cost of mass loss? to be more specific: When a power plant generates energy by burning gas or coal, a part of the particles in the fuel burned simply disappear and can't be found in the...

In a non-flow process, 0.6kg of steam at a pressure of 10 bar and a temperature of 235°C is cooled at a constant pressure in a cylinder. After 45 minutes the cylinder contains 0.12 kg of saturated water and 0.48kg of dry saturated steam. Calculate (a)the change in internal energy, the work...

Question 1 In a closed system, 0.6kg of wet steam at a pressure of 5 bar and a dryness fraction of 0.2 is heated at constant pressure until the volume occupied is 0.18m3. (A)Calculate the change in internal energy, the work energy and the heat energy transferred during the process. Question 2...

Hej, basicaly what I have is a program that calculates states of the gas in Carnot cycle (Jet engine). Now my intention is to plot it in T-S diagram. To do that, knowing the states after an each component of engine, I need to evaluate a temperature as a function of Enthropy change knowing only...

https://particle.phys.uvic.ca/twiki/pub/Main/AlisonFaulkner/Drell-Yan.jpg The Feynman diagram for Drell Yan has a gamma-star or a Z as the mediator. Does gamma-star simply mean a photon with a sizeable amount of energy? Is there a well-defined point in the energy of the mediator when it's a Z...

Hello. I plan on doing independent study on the Stochastic Process and time series models. I have already learned two semesters worth of statistics (Mathematical Statistics and Applications by Wackerly, Mendenhall and Scheaffer). And I have taken a semester of multiple regression models. I...

Homework Statement The problem, more like a riddle, that our teacher gave it to us was to find the error in this particular equation: integral of 1/x dc = ln (absolute value of (x)) + C ; perfectly fine integral of dx/3x = 1/3 integral of dx/x ; also fine 1/3 integral dx/x = 1/3 ln...

Homework Statement A two dimensional crystal process is modeled by an Avrami equation phi(t)= 1-exp(-k*t^2), where k>0. Experimental observation suggests that the inflection point of phi occurs at t=2 hours. Find the dimension and numerical value of k. Homework Equations I know how to...

I hope someone can put me on the right track here. I need to derive the infinitesimal generator for a bridged gamma process and have come a bit stuck (its for a curve following stochastic control problem - don't ask). Any tips, papers, books that could guide me out of my hole would be greatly...

Hi everybody. My goal is to design a process that, with no automated machinery (I'm using a mechanical pipette), would allow for extremely uniform coverage (that is, with minimal area of multilayers or empty spaces) of a hydrophilic surface with a thin film of polymer solution. I would...

Consider stochastic process ##X(t)## with properties $$ \langle X(t) \rangle = 0, $$ $$ \langle X(t) X(t-\tau) \rangle = C_0e^{-|\tau|/\tau_c}. $$ For example, the position of a Brownian particle in harmonic potential can be described by ##X##. In that case, the probability...

Let \phi(t) be a Brownian Walk (Wiener Process), where \phi\in[0,2\pi). As such we work with the variable z(t)=e^{i\phi(t)}. I would like to calculate E(z(t)z(t+\tau)) This is equal to E(e^{i\phi(t)+i\phi(t+\tau)}) and I know that E(e^{i\phi(t)})=e^{-\frac{1}{2}\sigma^{2}(t)}, where the...

Homework Statement Assume nitrogen gas (N2) is an ideal gas. n = 7.57 moles of N2 gas are heated isobarically (at constant pressure) from temperature To = 18.6 oC to temperature Tf = 50.9 oC. Find: c) ΔIE, the change in internal energy of the N2 gas Homework Equations Change in IE...

Homework Statement n = 1.46 moles of ideal gas are heated isobarically (at constant pressure) from temperature To = 431 oC to temperature Tf = 1227 oC. Find: change in Energy, Q, W. Homework Equations Change in IE = Q + W W (isobaric process) = P(vf-v1) The Attempt at a Solution...

Homework Statement n = 1.46 moles of ideal gas are heated isochorically (at constant volume) from tepmerature To = 649 oC to temperature Tf = 1184 oC. Find: a) Work done on the system. b) Change in Internal Energy of the system. c) The total heat, Q, added or removed from the system...

Homework Statement Is the process \{X(t)\}_{t\geq 0}, where X(t)=\rho B_1(t)+\sqrt{1-\rho^2}B_2(t) Standard Brownian Motion? Where \rho\in(0,1), \ B_1(t) and B_2(t) are independent standard brownian motionsHomework Equations The Attempt at a Solution Obviously X(0)=0. Now let 0\leq...

Homework Statement A large research balloon containing 2000 m^3 of helium gas at 1.00 atm and a temperature of 15.0 celsius rises rapidly from ground level to an altitude at which the atmospheric pressure is only 0.900 atm (the figure (Figure 1) ). Assume the helium behaves like an ideal gas...

Hi Guys I have problem to express the jump process as following ways. Please let me know your ideas~! Thank you so much. ------------------------------------------------------------------------- Let (Xt)t≥0 be an irreducible continuous-time jump process on a nite state space...

Has anyone come across an example where electromagnetic fields have been applied during crystallization processes. For example to modify crystal properties like magnetization or to change the polymorphism. In principle the use of electric / magnetic fields should change the formation of a...

I have the random process: Sequence 1: 0 0 1 0 0 1 0 0 1 0 0 1 0 0 1 ... Sequence 2: 1 0 0 1 0 0 1 0 0 1 0 0 1 0 0 ... Sequence 3: 0 1 0 0 1 0 0 1 0 0 1 0 0 1 0 ... where let nature choose one of these sequences at random with equal probability 1/3. Can we say anything about this...

A piston-cylinder assembly contains 20kg of air with a specific internal energy of 28K J/kg. It is compressed to a high pressure and the final specific internal energy is 65K J/kg. During the process there is a heat loss of 3.2K J. Determine the work energy input needed for the compressor...

I know carnot's cycle is an example. but what is it exactly? a cycle in which ever part of process has a 'counter-process' please elaborate.

Homework Statement Consider n moles of ideal gas kept in a cylinder with a piston. Two heat reservoirs 1 and 2 with the temperatures T1 < T2 are available, and at any given moment of time the heat exchange is established with only one of the reservoirs. In the initial equilibrium state the...

Homework Statement A system containing 10kg of water undergoes a reversible isothermal process. The initial state can be characterized as saturated vapor at 300°C. The pressure in the final state is 1MPa. The heat transfer during the process in (inKJ) Homework Equations Q = m(U2-U1)+W...

I tried this by the limit process but somewhere can't find my error wolfram says it is 128.25 any suggest or find error?:cool:

A number of aliens, who have just dropped in from another planet, emerge from the spacecraft . (i) There is more than one alien (ii) each alien has the same number of fingers (iii) each alien has at least one finger on each hand. (iv) the total number of fingers of all the aliens is...

hello, This is my first post (attempt 2) Question. What is the probability of a theory being correct or valid if it was made under the following circumstances? Conditions: Very little knowledge of science, just a curious mind. Not looking at knowledge that is known and came...

For reversible, work done =∫P dV Then for irreversible ,we can't use the above equation, because we have to consider the dissipative work. Correct? Thank you

Homework Statement Performance of a car wash center is modeled by the single-server Bernoulli queueing process with 2-minute frames. Cars arrive every 10 minutes, on the average. The average service time is 6 minutes. Capacity is unlimited. If there are no cars at the center at 10 am, compute...

I read on a website that by washing a precipitate with too much de-ionised water; the precipitate is Peptized and thus some precipitate is lost. I am having a hard time understanding what peptization is? Can somebody please help me understand in simple terms for an A level student?

Why does: \int_0^t d(e^{-us} X(s)) = \sigma \int_0^t e^{-us} dB(s) for stochastic process X(t) and Wiener process B(t)? Also, why is the following true: \int_0^t d(e^{-us} X(s)) = e^{-ut}X(t) - X(0)

Is it true that d\int_0^t s dB(s) = tB(t)? If not, why not? If not, what's the correct answer? I've googled extensively for how to find the derivative of an integral, but all sources talk about preceding the integral with \frac{d}{dx}, but I'm preceding it with only d.

Homework Statement Suppose that W_t is a Wiener process (i.e. standard Brownian Motion). Is it true that W_t = \mathbf{1}_{\{W_t \geq 0\}}W_t + \mathbf{1}_{\{W_t < 0\}}W_t ?The Attempt at a Solution No idea. This isn't even homework it's part of my attempt of a solution to a homework...