Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Is mechanical energy conservative?

  1. Dec 18, 2004 #1
    is mechanical energy conservative?
     
  2. jcsd
  3. Dec 18, 2004 #2

    arildno

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member
    Dearly Missed

    No, the mechanical energy of a system might, occasionally be conserved; "conservative"/non-conservative is a way to classify FORCES.
     
  4. Dec 18, 2004 #3

    Doc Al

    User Avatar

    Staff: Mentor

    I assume you mean: Is mechanical energy conserved? Answer: Sometimes! :smile:

    For example: A block sliding down a frictionless incline--mechanical energy (PE + KE) is conserved; but introduce friction, then mechanical energy is not conserved.

    Did you have a particular situation in mind?
     
  5. Dec 18, 2004 #4
    sliding a block on a flat table. I saw that there wasn't a change in Kinetic Energy. So, that means energy is not conserved. I know that the friction force is non-conservative but I wasn't sure about the mechanical energy.
     
  6. Dec 18, 2004 #5

    Doc Al

    User Avatar

    Staff: Mentor

    Why would seeing the KE not change lead you to think that energy was not conserved? :confused:

    Mechanical energy is not a force.
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook