Read about thermodynamics | 495 Discussions | Page 17

  1. O

    Heating the mixture

    In a thermally insulated container was a mixture of ice and water. Then we have put a immersion heater ( P=400W). We started measure time and at the end of every minute we writed down the heat od mixture. First two minutes the heat wasn't changing, at the end of third it raised about 2°C, at the...
  2. B

    Research Help Please -- "Ziemlich Frech : Einstein versus Nernst"

    I am writing an essay on "Ziemlich Frech : Einstein versus Nernst". I can find very little information on this topic anywhere. I've searched the library and the internet and don't have anything certain yet. So far I'm at a stage where I believe it could be about Einstein Solids. I know that...
  3. A

    Joule-thomson effect and linde process

    According to the j-t effect the decrease in the temperature is a result of the work done by molecule to expand thus increasing their PE and decreasing their KE, but in the linde process the next step is liquification, i am having trouble understanding how it happens, since the intermolecular...
  4. B

    Thermodynamics Chemical Potential

    Homework Statement Consider a monatomic ideal gas that lives at a height z above sea level, so each molecule has potential energy mgz in addition to its kinetic energy. (a) Show that the chemical potential is the same as if the gas were at sea level, plus an additional term mgz: μ(z) =...
  5. B

    Thermodynamics atmospheric pressure Question

    Homework Statement A liter of air, initially at room temperature and atmospheric pressure, is heated at constant pressure until it doubles in volume. Calculate the increase in its entropy during this process. so Ti= 300K, Volume which is 2Vi=Vf; Pressure is constant Homework Equations ΔS...
  6. P

    Non-quasistatic process. Constant pressure.Work cero.

    If in a non-quasistatic process the pressure is constant, is the work necessarily equal to cero? I have from the notes taken in class that it must be 0, but I don't really see why, so I'm not sure whether maybe I didn't hear it well. I haven't really started to work with non-quasistatic...
  7. SalfordPhysics

    Thermal Conductivity of Steel experiment

    1) PROBLEM: Task is to find the thermal conductivity of steel experimentally. I have conducted relevant experiments and I am trying to solve for the thermal conductivity (k) itself. My final however is ten times too large in size, and I am having trouble identifying where the error is coming...
  8. A

    Steady Flow Energy Equation basics

    Right, I'm sure this is bread and butter to a lot of you but I have just been introduced to the SFEE. mgz+0.5mC^2+H +Q = mgz + 0.5mC^2 +H+W Where Q is the heat transfer, W is work done and H is enthalpy. Where is it assumed that the heat energy is in the energy balance? If heat is added where...
  9. mef51

    [Thermodynamics] Heat Capacity for Polytropic Process

    Consider an ideal gas. For a polytropic process we have ##PV^n = const##. Different values of ##n## will represent different processes; for example isobaric (##n=0##), isothermal (##n=1##), and isochoric (##n=\infty##). The Wikipedia article on polytropic processes states that the specific heat...
  10. 1

    Enthalpy's physical interpretation

    Hi I'm new to this site, so I'm not sure where to post this question but chemistry seemed fitting. I'm current taking 2 thermo classes, engineering and chemistry, and I'm having trouble with the concept of enthalpy. This is what I believe I understand. I Hope the following is all correct if...
  11. A

    Ideal gas

    Homework Statement http://puu.sh/c0rhe/fb6b48f890.png [Broken] Homework Equations PV=constant The Attempt at a Solution I have no idea how to apply the above equation. Please help.[/B]
  12. A

    Thermodynamics question

    Homework Statement Homework Equations Conceptual qn The Attempt at a Solution work is done in gas but how can internal energy change? there is no heat flow since it is an adiabatic process[/B]
  13. G

    Thermodynamic cycle p-v to T-s

    Homework Statement I have been given a description of a thermodynamic cycle that looks like this. I have two polytropic processes (n1=1.2, n2=1.9), and one isochoric. The known data are: p1 = 1 bar T1 = 15 °C p2 = 15 bar Homework Equations p v^(1.2) = 0.7958 p v^(1.9) = 0.69657 The Attempt...
  14. A

    Thermal Expansion of a shrink-fit collar

    Looking for some information on how a shrink fit collar actually works. I get the basic principle that you heat it, it expands, fit the collar, let it cool and it contracts and grips as a collar. However, if you heat a material am I right in saying that it expands in all direction. If this is...
  15. C

    Carnot cycle problem - Is it thermodynamically possible to do 500J of work?

    Homework Statement 2. The attempt at a solution Is it only possible when 600J of heat is exhausted and 400J of heat is converted into work? Is the 600J heat will enter the cold reservoir and available to do work again? q1/T hot + q3 / T cold = 0 q3 = 600 when T = 300K
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