Process Definition and 1000 Threads

the wave/particle duality is no more seen as the opposite sides of a coin. We now see it as a point in a segment [0 , 1]. It is the same with pure states. The visibility of the fringes varies between 0 and 1. In regards to measurement, We are often in the old yes/no habit: At a some point the...

I'm struggling to understand a concept which I assume is basic, but I can't seem to fit the pieces together. When speaking about an ideal gas, I understand that ΔH = ΔU + Δ(PV) = ΔU + RΔT So far so good. I also understand the relationship: ΔU = Q + W... (W here is work being done on the...

Why does ∆S = 0 for a reversible process, but for a reversible isothermal process, ∆S is given by nRln(Vf/Vi) (or other variations of that equation)?

I have a gas transitioning adiabatically between A (P1, V1) and B (P2, V2) where P1>P2 and V2>V1. The question is to determine the net work done on the gas if the gas is first expanded reversibly from A to B (w = dE = Cv(T2-T1)), and then compressed irreversibly from B to A (w = -Pext(V1-V2)) at...

hello brothers and sisters, i have got a project on making an agriculture shredder, i am having difficulty in finding the general equation for the force required to perform cutting operation can anyone help me out

Hi Guys, I am having issues trying to repair this amp. http://www.tangible-technology.com/schematics/fender/HR-Deville/Hot%20Rod%20DeVille.pdf A little history is in order I guess. I have not been working on guitar amps for too long, several months now. I have repaired perhaps fifty or so...

Homework Statement "Determine the polytropic process index 'n' from the initial and final condition parameters of the air (gas) in the air compressor cylinder." Im struggling with this question on my thermodynamics coursework and was wondering if anyone could help me out a little bit...

Homework Statement A well insulated container consists of two equal volumes separated by a partition - one half an ideal gas while the other is a vacuum. The partition is removed, and the gas expands. What is the entropy change per mole? Homework Equations dS = dQrev/T S/R = Cp/R dT/T -...

Homework Statement An amount of water substance having a mass of 1 kg is contained in a vessel at a pressure of 1 MPa. It is heated for some time after which the pressure is 3 MPa. The volume of the vessel is 0.1 m3. Assuming no work is done by or to the substance, calculate the final...

1. Homework Statement When volume changes from V to 2V at constant pressure then the change in internal enrgy will be? 2. Homework Equations ΔU= nCvΔT 3. The Attempt at a Solution I have used the equation ΔU= nCvΔT but the answer is PV/γ-1

Homework Statement Let $$ \Phi(x)=\int_{-\infty}^{x} \frac{1} { \sqrt{2\pi} } e^{-y^2 /2} dy $$ and $$ \phi(x)=\Phi^\prime(x)=\frac{1} { \sqrt{2\pi} } e^{-x^2 /2} $$ be the standard normal (zero - mean and unit variance) cummulative probability distribution function and the standard normal...

Homework Statement 3. The Attempt at a Solution [/B] ***************************************** Can anyone possibly explain step 3 and 4 in this solution?

Hello! Can someone please help me with finding a full explanation on the production (manufacture) process of microspectrophotometers? I need to do a presentation on microspectrophotometers and I have a problem with finding this information. Thanks!

When CLAS of Jlab describe the result of the process ep→epπ,the use the terminal "transverse amplitude" Ml±(W,Q2), El±(W,Q2),and "scalar(longitudinal) amplitudes"Sl±(W,Q2),they correspond to photons of the magnetic, electric, and Coulombic type.Are they observables? The index of...

Homework Statement Let X(t) be a birth-death process with parameters $$\lambda_n = \lambda > 0 , \mu_n = \mu > 0,$$ where $$\lambda > \mu , X(0) = 0$$ Show that the total time T_i spent in state i is $$exp(\lambda−\mu)-distributed$$ 3. Solution I have a hard time understanding this...

Homework Statement Insects land in the soup in the manner of a Poisson process with intensity lambda. Insects are green with probability p, independent of the color of the other insects. Show that the arrival of green insects is a Poisson process with intensity p*lambda. Homework Equations3...

Homework Statement [/B] You are asked to calculate changes in internal energy, entropy, heat transferred and work done for each of the following process. Also you are asked to calculate "the latent heat for the isotherm in the figure". We know the a and b parameters which characterize the VdW...

I have been studying a processing time for an industrial process. The present analysis just consists of finding the mean value as if the time was distributed normally. I took a sample of data and made a histogram of the data and realized it is not normally distributed at all. The normal...

ohk, let me make it more clear for you, the situation is we have a boiler generating steam at 23.5 barg, which is throtlled down to 12 barg for import/ export, this 23.5 barg steam is throttled down to 3 barg by another valve to use in heat exchanger, and then this 23.5 barg steam is throttled...

Hi there, I just sign up today. I'm curious to know about the energy added/released in a Carnot Refrigeration Cycle. Let's say the problem is like this: A Carnot Refrigerator used refrigerant-134a as the working fluid. During the heat addition process, a percentage of mass of the refrigerant...

Homework Statement A 20 kg sample of mercury is completely solidified and liberates 231.6 kJ of energy. What is the original temperature of the mercury? (The melting point of mercury is 234K, the heat of fusion of mercury is 11.3 kJ/kg, and the specific heat of mercury is 140 J/kg•K.) . What is...

Homework Statement An ideal Carnot process operates between a heating bath with the temperature of 20 C and a mole of hydrogen is in a container with constant volume. During the process, the work is done to remove heat from the hydrogen gas and emit heat to the heat bath. Calculate the work...

Dear PF Forum, My church concerns about climate change/global warming condition now. And we try our best to cope (altough in a very small scale) to lessen the effect. Now, I'd like to know about composting. But I have no idea what to do. What stages are there in composting What kind of bacterias...

Lets say we have T1. From a reservoir 4000K, Q is added and that makes the temperature T2. How do we calculate the entropy generation in a process like that? Isn't it Sgen=S2 - S1 - (Q/T) But which temperature we will use in the (Q/T)? T1, T2 or 4000K?

Hello, So I was asked this question the other day and don't really know how to go about it: "Define a random process by: Xn+1 = Xn+1 with probability 1/2 Xn+1 = 1/Xn with probability 1/2 Given that X0= 100, find the expectation of X10 " I've only ever really met random processes...

Hello guys, Suppose a process 1+2--->3+4 proceeds thru 3 different intermediate particles and has 3 Feynman diagrams. When we compute the probability then what does the cross terms( interference ) mean? and do we have to always compute the cross terms? What I mean is that when you have 3...

Hello everyone, I still wonder if there's a change in entropy in adiabatic process. The definition of entropy is a quantity represents for the disorder state of a system. Arccording to kinetic theory of gas, temperature is for the state of chaotic motion of molecules. So I'm very confuse, can...

If throttling reduces mass flow rate then how can we say it as steady flow process where the mass flow rate is constant?

. Homework Statement Q1. Let f(x) be any continuous function that satisfies: $$-2x≤xg(x)≤2x$$ for $$0≤x≤1$$ Find the upper and lower bounds for: $$\int_{0}^{1} \sqrt{1+g(x)+x^2}dx$$ Q2. Let h(x) be any continuous function that satisfies: $$-4≤h(x)≤x^2-4$$ for $$0≤x≤1$$ Find the upper and...

Homework Statement http://i.imgur.com/jmLqca9.jpg pic of question Homework Equations W = p x dV, Q = dU + W etc The Attempt at a Solution I know what the different stages are, a-b and c-d are isobaric, d-a and b-c are isochoric and I believe the answer to a, the net work done in one cycle...

I already done an experiment for detecting the presence of heavy metals(copper and lead) . The last step for detection is through the absorption of analyte by atomic absorption spectroscopy. Before that step to be done, the first process is to digest the water sample in the fume chamber...

Hi all. I've been getting up to speed with Gaussian processes (https://en.wikipedia.org/wiki/Gaussian_process), and was interested to know what properties a Gaussian process must satisfy for it to also be a Markov process (https://en.wikipedia.org/wiki/Markov_process). Briefly, a Gaussian...

Assuming that we have a chemical plant which produces methanol through the following equations: CH4 + H2O <--> CO + 3H2 CO + 2H2 <--> CH3OH CO2 + 3H2 <--> CH3OH + H2O I know that with specific pressure, temperature and flow rates, I can produce reactions with specific equilibrium constants. Are...

Even though entropy is a state function and thus independent of path why is it that the definition of entropy is restricted to a reversible process? Eq 1: dS=dqrev/T First of all, is this for an open system, closed system or isolated system? The Clausius inequality deals with the exchange...

A manufacturer has designed a process to produce pipes that are 10 feet long. The distribution of the pipe length, however, is actually Uniform on the interval 10 feet to 10.57 feet. Assume that the lengths of individual pipes produced by the process are independent. Let X and Y represent the...

Homework Statement Problem: A sample of dry air has an initial pressure p1 = 1000 hPa and temperature T1 = 300K. It undergoes a process that takes it to a new pressure p2 = 500 hPa with unchanged temperature T2 = T1. Compute the mechanical work per unit mass perfromed by the sample under the...

Homework Statement Calculate: PLIM (probability limit) \frac{1}{T} \sum^T_{t=2} u^2_t Y^2_{t-1} Homework Equations Y_t = \rho Y_{t-1} + u_t, t=1,...T, |\rho| <1 which the autoregressive process of order 1 E(u_t) = 0, Var(u_t) = \sigma^2 for t cov(u_j, u_s) = 0 for j \neq s The Attempt...

We have an ideal gas enclosed in cylinder whose top is covered by a piston of certain weight ##mg##. At this stage, the piston is at rest which means the force by which the gas acts on the piston (##F=PA## where ## P## is the gas pressure and ##A## is the cross sectional area of the cylinder) is...

I am facing some overwhelming doubts while trying to study 'Psychrometrics'.Currently I am bamboozled trying to understand the process of[FONT=Georgia] adiabatic saturation of moist air. Some of the textbooks claim that a true adiabatic saturation process proceeds along the line of constant...

Homework Statement Differentiate Homework EquationsThe Attempt at a Solution du/dx = cos(x) dv/du=cos(u) dg/dv=cos(v) dg/dx = dg/dv.dv/du.du/dx = cosx.cos(sinx).cos(sin(sinx)) I know the answer is correct but my issue is in the understanding of the...

Homework Statement A specific type of ideal gas has a specific heat capacity at constant pressure (cp=cv+R) that is a function of temperature T, such that cp=0.5+876T, where cp has units of J/kg/K and T has units of K. The gas, which is initially at T1 = 294 K and P1 = 1x105 Pa, undergoes a...

In conjunction with diving, a mixture of helium and oxygen called heliox. It will form the background to the following model invoice. Suppose that 1 mole of He and 1 mole of O2 is compressed as fast at half the volume that no heat exchange with the environment have time to take place...

In psychrometrics it is outlined time and again that we cannot achieve a pure humidification process i.e, add only moisture to unsaturated air without a change in its Dry Bulb Temperature(DBT).While pondering over the idea I came up with a possible way of doing it (if it is correct at all) and...

This reminds me of the old mastermind puzzle. Computer picks (at random) a 4-digit number. The number will contain only the digits 1, 2, 3, and 4: the digits may be used more than once: 1111 to 4444. You input a guess as to what the number is. If your guess has at least 3 digits in their...

In an adiabiatic process q=0 so change in internal energy become equal to work. Since internal energy is path function so work done in an adiabiatic process should also be path function then why work done in adibiatic reversible and irreversible different?

In the mix solvent of recrystallization, why it is better to add the second solvent dropwise instead of by one-portion? i think...is it to improve the purification? but why?? is it increase the time of contacting the solvent so as to achieve a better dissolution??

Homework Statement I need to write an equation for the at rest at a stoplight. Each car bumps into the one in front of it until the first car in line gets bumped. Homework Equations I found these equations for wave speed: V=√(T/(m/L)), where T is tension, m is mass, L is length and of...

Homework Statement An ideal diatomic gas is initially at temperature ##T## and volume ##V##. The gas is taken through three reversible processes in the following cycle: adiabatic expansion to the volume ##2V##, constant volume process to the temperature ##T##, isothermal compression to the...

The structure of the Paramecium is rather complicated. Its plasma membrane is specially equipped with thickenings, so the membrane can be strengthened. Then, this membrane is called the pellicle. A paramecium has one big nucleus and two smaller nuclei. The bigger nucleus is about nutrition, and...

Homework Statement A sample of an ideal gas goes through the process shown in Figure P20.32. From A to B, the process is adiabatic; from B to C, it is isobaric with 100 kJ of energy entering the system by heat. From C to D, the process is isothermal; from D to A, it is isobaric with 150 kJ of...