A community for students.

Here's the question you clicked on:

55 members online
  • 0 replying
  • 0 viewing

anonymous

  • 4 years ago

why the internal energy is 0 in case of isolated system? I mean, how the dq and dw are both 0

  • This Question is Closed
  1. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    internal energy is not zero, internal energy is a CONSTANT, hence the CHANGE in the internal energy is zero!!

  2. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    oh sorry ...i meant the same... how dW is 0

  3. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    well.. actually.. in an isolated system, i don't think the internal energy is a constant.. infact only dq is zero.. because no energy is allowed to flow in or out ( hence the term isolated), so there will be change in internal energy and it ll be used to do some work, so by using the first law of thermodynamics we have dq= dU + dW hence we put dq= 0 so dU= -dW.. and thus.. the work is done BY the system ( negative sign implies that).. an example of this would be an adiabatic process!

  4. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    u r right but u explained a closed system here...what abt isolated system??? in which dq is also 0 and dw=0 ... is it bcz of this..? dU=0 (bcz isloated system no heat supplied so, dq=0 and since, dU= dQ+dW so 0=0+dw => dw=0

  5. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    but my problem is how internal energy is 0 here

  6. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    internal energy is never zero.. i told you.. its a CHANGE that is zero.. !!

  7. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    If you consider an isolated system.. no energy is given to it, and no energy is given out from it as well.. hence how can it do work?

  8. anonymous
    • 4 years ago
    Best Response
    You've already chosen the best response.
    Medals 0

    may be its process is adiabatic,so W no 0

  9. Not the answer you are looking for?
    Search for more explanations.

    • Attachments:

Ask your own question

Sign Up
Find more explanations on OpenStudy
Privacy Policy

Your question is ready. Sign up for free to start getting answers.

spraguer (Moderator)
5 → View Detailed Profile

is replying to Can someone tell me what button the professor is hitting...

23

  • Teamwork 19 Teammate
  • Problem Solving 19 Hero
  • You have blocked this person.
  • ✔ You're a fan Checking fan status...

Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.

This is the testimonial you wrote.
You haven't written a testimonial for Owlfred.