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Homework Help: How much energy would neon gas absorb to increase the temperature

  1. Feb 11, 2006 #1
    i have 3 questions that i need help with

    Consider 180 g of neon gas. How much energy would it have to absorb to experience a temperature increase of 12 K?

    Construct a PV diagram for each of the following. (a) A gas begins with a volume of 14 L under pressure of 3 atm. The gas first undergoes an isobaric compression to a volume of 6 L. Next, the gas experiences an isothermal expansion back to a volume of 14 L. (b). A gas undergoes a cyclic process consisting of two isochoric processes and two isobaric processes.

    A particular engine having efficiency 27% operates at temperature 420C. What is its highest possible exhaust temperature?

    thanks ron
     
    Last edited: Feb 11, 2006
  2. jcsd
  3. Feb 11, 2006 #2

    Astronuc

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    Staff Emeritus
    Science Advisor

    One needs to show one's work before requesting help.

    However, some hints:

    1. The energy is related to the mass, the specific heat and the change in temperature. An example should be found in one's text book.

    2a. P-V diagrams are fairly straight forward. The problem starts with a known state point, P, V. Isobaric means 'constant' pressure, and on is given the new volume of 6L. Isothermal is constant temperature, so one needs to find the relationship of P and V for an isothermal expansion.
    Isobaric process - http://www.pha.jhu.edu/~broholm/l35/node4.html [Broken]
    Isothermal process - http://www.pha.jhu.edu/~broholm/l35/node3.html [Broken]

    2b. An isochoric process, also called an isometric process, is a thermodynamic process in which the volume stays constant; ΔV = 0.
    See - http://en.wikipedia.org/wiki/Isochoric_process
    and - http://www.pha.jhu.edu/~broholm/l35/node2.html [Broken]

    3. Find the definition of Carnot efficiency as a function to the hot and cold temperatures, Thot and Tcold, respectively.
     
    Last edited by a moderator: May 2, 2017
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