Process Definition and 1000 Threads

  1. S

    Can adiabatic process be isothermal process?

    i'm entirely confused with this. with analyzing each definition: adiabatic process : a thermodynamic process in which there is no transfer of heat if a system is in state (P1, V1, T1) → (P2, V2, T2) if it is adiabatic no heat transfer occurs, if no heat transfer occurs the two states must be...
  2. S

    Question related to IID process

    Hi. I have a question about and IID process (attached). I'll be happy if someone could help me understnad it better. Thanks in advance :shy:
  3. J

    Heat transferred during an infinitesimal quasi static process of an ideal gas

    Homework Statement Show that the heat transferred during an infinitesimal quasi static process of an ideal gas can be written as dQ = (Cv/nR)(VdP) + (Cp/nR)(PdV) where dQ = change in heat Cv= heat capacity while volume is constant n= number of moles of gas R= ideal gas constant Cp=...
  4. G

    Irreversibility of a Process: Finding ΔQ and ΔS of a Mass Dropped into the Sea

    Homework Statement A mass m with heat capacity c at temperature T_1 is dropped into the sea at T_2. What is the irreversibility of the process? Homework Equations I = T_0 (\Delta S + \Delta S_E ) I = W_{\text{rev}} - W The Attempt at a Solution Heat in is Q=mc\Delta...
  5. R

    Process to form elements in quantity

    Do macro amounts of elements form when atoms of a certain type (e..g. gold) bond together to form a substantial mass? Or do atoms of mixed types bond together and then together take on the properties we ascribe to each element? The reason I ask is that it seems improbable to me that a few...
  6. I

    Internal Energy and Work Done in an Adiabatic Process

    Homework Statement The question is as following: http://i56.tinypic.com/se547s.png Homework Equations W = F x distance or p d(v) . Potential energy : mgh , k.e : 1/2mv^2 The Attempt at a Solution Well I am stuck on part c, now I am aware that in adiabatic process Internal...
  7. I

    Adiabatic process - Diesel engine

    Homework Statement A diesel engine requires no spark plug. The air in a cylinder is compressed so highly that the fuel spontaneously ignites when sprayed into cylinder. If the air is initially at 20°C and is then compressed by a factor of 15 in volume, what final temperature is attained...
  8. C

    Polytropic process where n is not given

    Hi I really need help figuring out this problem. A balloon behaves such that the pressure inside is proportional to the diameter squared. It contains 2 Kg of ammonia at 0 degrees celcius and 60% quality. The balloon and ammonia are now heated so that a final pressure of 600 kPa is reached...
  9. J

    The work done by an adiabatic process?

    Homework Statement On my formula sheet I have this: W=(C/1-y)(Vf^(1-y)-Vi^(1-y)) y=Cp/Cv Homework Equations The Attempt at a Solution I am confused about what the C in C/1-y stands for. My textbook does not even have this formula and I realized that C is not Cp or Cv...
  10. J

    Work Done in a polytropic process

    Homework Statement A gas is trapped in a cylinder-piston arrangement. The initial pressure and volume are 13,789.5 Pa and 0.02832 m^3. Determine the work(kj) assuming that the volume is increased to 0.08496 m^3 in a polytropic process with n=1. Homework Equations m_1-2=∫PdV from 1 to...
  11. S

    Calculating Final Pressure in Isochoric Thermo Process

    I'm trying to calculate the final pressure. I was given initial and final temperatures as well as initial pressure, expansitivy and isothermal bulk modulus. I was also told the volume is constant. Since volume is constant I figured dV=0 so in the formula dV=VβdT - VKdP it reduces to...
  12. P

    Admissions Getting Into MIT to the Application Process

    Anyone knows how to get admission in MIT ??
  13. J

    What Happens to Enthalpy in Constant Volume and Pressure Processes?

    enthalpy is defined as h = u + pv so, dh = du + d (pv) if the process is constant pressure, dh = du + p dv (change in internal energy + boundary work ) during constant pressure process, if heat is added to the system, it increases its internal energy as well as it does the...
  14. C

    Are textbooks sloppy with the entropy change of an irreversible process?

    Trying hard to understand a basic textbook model meant to illustrate that entropy (of the universe) increases for irreversible processes. Help me out please? I get this part: A gas is compressed isothermally (constant T) and reversibly, getting worked on and expelling heat. To calculate ΔS...
  15. H

    Filling Flat Tire - Adiabatic Reversible Process

    Homework Statement A nearly flat bicycle tire becomes noticeably warmer after it has been pumped up. Approximate this process as a reversible adiabatic compression. Take the initial P and T of the air (before it is put into the tire) to be 1.00 bar and 298.0K. The final volume of air (after it...
  16. W

    Steel Making process (always half explained)

    Hi, I want to try and make some steel alloy in an induction furnace. I have gone through youtube, Engineering Books, Internet and yet I haven`t found an answer that will completely explain how to make steel alloy. In what form are the components like Si, P, Mg, Mn etc added to...
  17. M

    Ideal Gas Under A (Complex) Reversible Process

    Homework Statement An ideal gas undergoes a reversible process 1-2-3-4-5. The stage from 1-2 as well as isobaric 2-3 and isochoric 4-5 stages are represented by linear segments. The Stage 2-3 is isothermal. The following relations are true: V_2=2*V_1 p_2=1.5*p_1 V_3=4*V_1 V_4=6*V_1...
  18. P

    How Do Microprocessors Process?

    I am just curious how a microprocessor is able to actually process data. A serious of voltage variations corresponding to bits flows into it, but how does the inanimate slab of etched silicon "know" how to act on it and what to do with it? I am just in awe that computers can even work at all...
  19. L

    Thermaldynamics problem, reversible process work done on

    Homework Statement One mole of a monatomic ideal gas is taken through a reversible process from an initial state "a" to a final state "b" during which the pressure of the gas varies with volume V as shown below. Calculate the work Won[/on](a->b) done on the gas during this process...
  20. O

    Reversable process with adiabatic expansion

    Homework Statement One mole of a monatomic ideal gas is taken through the reversible cycle shown below. http://img508.imageshack.us/img508/2595/newbitmapimageqm.png process bc is an adiabatic expansion, with P_b = 10.00 atm and V_b = 10^-3 m^3. Find (a) the energy added to the gas as heat...
  21. U

    Entropy change in a reversible isothermal process.

    Homework Statement In a reversible isothermal expansion of an ideal gas, as the gas expands, heat is supplied to it, so that the temperature remains constant. Thus, temperature and hence kinetic energy of the molecules does not change but the 'disorder' of the gas increases as it occupies a...
  22. A

    Haber process and power generation

    Is the Haber process ever used to generate electricity? I recognize that it's not an efficient means, because of the amount of energy needed to create H2 gas, but because the actual Haber process is exothermic and is less efficient once the temperature creeps above 400 degrees, why shouldn't it...
  23. M

    Questions regarding sputtering machines, their magnetrons, and etch process

    Hello, Years back, I used to work with a sputtering machine, but I never really understud some of the activities within the machine. One of the things that puzzled me was why the target was to be eroded, while the surrounding metal structure that held it in place and formed the lid, was not...
  24. A

    Ideal gas PV diagram heat transfer process

    Homework Statement There is a Pressure-Volume diagram of an ideal gas. The processes make up a (rough) triangle. At constant pressure, we have point A to point C to the right of it to point D to the right of C. Then above A we have point B. C goes to B and D goes to B.. thus forming something...
  25. D

    Stages in the deformation process

    The deformation process involves different stages. I was wondering how do you call the process where the materials return to their orginial state? Just as given in the bold text. And, moreover, what is the formula which calculates the time it returns back to the orginal state for a random...
  26. A

    Conservation of Energy/momentum in Photoelectric process

    Homework Statement Show that a free electron cannot absorb a photon and conserve both energy and momentum in the process. Hence, the photoelectric process requires a bound electron. (Eisberg and Resnick 2nd Ed) Homework Equations hv = E p = K / c E2 = (pc)2 + (m0c2)2 The Attempt...
  27. M

    Why the process of recombination is called re combination?

    Why the process of recombination is called "re"combination? The process in which the nucleus and electrons combined to form neutral atoms at early times is called recombination. But why it is added an "re" to "combination"? Is there any combination process before this process? Thx!
  28. A

    How to read data from files and process it?

    Dear all, I want to read data from a file which has four column and process the data for further calculation. After running the code it keeps given me 0.00000 as output. What do i do? Here is the structure of the code program new Implicit none integer,parameter ::Nmax=1000 Integer ...
  29. D

    What is the process to acheive hadronization?

    I am interested to know how to achieve hadronization (the specific details). Is anyone aware of a site where I could find this information (presented in a readable format)? I am also interested to know what types of hadron clusters result from this event. Thank you for any help you might...
  30. K

    Molecular work in an Adiabatic process ?

    Molecular "work" in an Adiabatic process ? I have studied Adiabatic cooling in connection with a rising parcel of air. I’m confused. I understand that temperature is a macroscopic principle (not a Microscopic); molecules do not have a temperature, only velocity and Kinetic energy. I have read...
  31. T

    A possible case of an irreversible process in which total entropy decreases

    When a hot stone is dropped into a lake the change in temperature of the lake is negligible, but the stone cools down and so its entropy decreases. Is this therefore a case of an irreversible process in which total entropy decreases? This isn't for homework but for revision towards my resit. I...
  32. C

    Why are real life process irreversible

    From what I've read all processes of a thermodynamic system are irreversible because some energy will be lost to the surroundings but I don't understand why that can't be reversed by getting the surroundings to put that energy back into the system. Let's say I have a gas canister with a piston...
  33. N

    Spherical Vector Addition Process

    Hello Everyone, I was just wondering if there was a way to add two vectors that are determined by spherical coordinates (radius, theta, phi). For example, if I have v1 = (5, Pi/4, Pi/2) and v2 = (3, Pi, -Pi/2) is there a way to add these using their respective radii, thetas, and phis or do I...
  34. L

    Mathematica Gillespie Algorithm (Monte Carlo Simulation) for simple process in Mathematica

    I am trying to model a simple birth and death process in Mathematica using the Gillespie Algorithm. I am using 1 DNA molecule that is transcribed to mRNA with rate k1, \mbox{DNA} \longrightarrow \mbox{DNA + RNA} and the transcribed RNA are subject to degradation with rate k2...
  35. V

    How to find maximum work done in an adiabatic process?

    My Question - Steam at 200 psi and 600 F flows through a turbine operating adiabatically and exits at atmospheric pressure. For every kilogram of steam flowing through the turbine there are 150 Btu of shaft work delivered. (a) What is the final condition of the exit steam? (b) What is the...
  36. M

    Energy Conservation in Quasistatic process

    Alright, this might sound stupid, but let us imagine a scenario. I bring an object from height 10 m to 4 m such that the velocity of the object remains constant. Due to this the potential energy of the object decreases. Now my question is, where does this energy go?
  37. W

    Limit Process Summation Confusion

    Hi, I have been staring at this for a while. I under stand the process and can account for and reproduce every step of this problem EXCEPT I can nit figure out where the 6i/n coms from. I have included the equation and the issue is highlighted in yellow. Please explain... this is the last...
  38. C

    Schools Admission process in Russian universities

    [FONT="Times New Roman"][SIZE="3"]The admission to Russian universities is open. Here is some information on general steps of application for a study in Russia. For getting in contact with the university you may send just of the documents by E-mail. Application packege consists of application...
  39. L

    Linear Algebra Matrix Limits/Stochastic Process

    Homework Statement A diaper liner is placed in each diaper worn by a baby. If, after a diaper change, the liner is soiled, then it is discarded and replaced by a new liner. Otherwise, the liner is washed with the diapers and reused, except that each liner is discarded and replaced after...
  40. A

    How does Helicase unwind the dna strands?what is the chemical Process

    how does Helicase unwind the dna strands?what is the chemical Process involved?what is the chemical reaction?
  41. S

    Irrev. adiabatic process entropy >0 or =0?

    My textbook says that Delta S (sys) > 0 for irrev. ad. proc., closed syst (or see http://www.britannica.com/EBchecked/topic/5898/adiabatic-process if you don't believe me) but since Delta S = 0 for reversible adiabatic process and entropy is a state function, shouldn't Delta S = 0 for...
  42. M

    Number of decayed atoms in a simultaneous decay process

    A certain amount N_0 of a radioactive isotope with decay constant \lambda_1 is injected into a pacient. Besides that isotope's natural decay process, there's also a biological elimination process, with decay constant \lambda_2. Now, at time t, the number of remaining isotope atoms is given...
  43. A

    Calculating Probability in Poisson Process Problem | Z(t-c)=m, Z(t)=k

    Given a poisson process Z(t) with a given rate lamda, k and m nonnegative integers and t and c real and positive numbers, calculate the probability: P(Z(t-c)=m | Z(t)=k) thanks
  44. J

    Efficiency of the heating process

    120MJ of heat are used to heat up a 1100kg component from 22oCelsius to 180oCelsius, in 1 hour, prior to heat treatment. If the specific heat capacity of the components material is 500J/kg, calculate the efficiency of the heating process. Please could somone give me the equation that i need...
  45. G

    Finding Horizontal Asymptote Process

    Homework Statement Find the horizontal asymptote of f(x) = (x2-1)/(x2-4) Homework Equations Limits The Attempt at a Solution I'm pretty family with the process, I just get confused when there's an x2 in the denominator and no x in the numerator ): So I already figured out that...
  46. E

    Understanding the Geometric Interpretation of the Gram-Schmidt Process

    Hi, What is the geometric interpretation of the Gram-Schmidt orthonormalization process? I mean, you will find everywhere that the procedure is as follows: 1. set u1=a1 => e1=u1/||u1|| 2. u2=a2-<a2,e1>e1 => e2=u2/||u2|| . . . As a comment on the second line, you will read that this...
  47. H

    Electromagnetic energy injected into combustion process?

    Hmm, not sure if this is the right place to be asking this. I am wanting to understand what effects electromagnetic energy can have when injected into the combustion process of hydrogen and oxygen? Can anyone tell me or point me what effects can occur or point me in the right direction to...
  48. M

    Characteristic Function of a Compound Poisson Process

    Hello, I am trying to find a characteristic function (CF) of a Compound Poisson Process (CPP) and I am stuck :(. I have a CPP defined as X(t) = SIGMA[from j=1 to Nt]{Yj}. Yj's are independent and are Normally distributed. So, in trying to find the CF of X I do the following: (Notation...
  49. O

    Designing Process for a Temperature Controlled Box

    [FONT="Arial"]Hey all! I am thinking of building a box in which the insides can be held a constant temperature. I would like to see if I can determine some parameters for the box. My first step is to determine heat loss through the box. I'm estimating that the largest difference in heat...
  50. L

    Could someone please explain the geometrization process?

    While reading about Minkowski's description of the fourth dimension time axis, I saw that by taking the product of the speed of light and time, he was able to give it a "spatial" geometric character of distance (i.e. light-years, light-seconds, or whatever). I then saw that he set c (the speed...
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