1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
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: Kinetic energy -- plot molecule frequency vs temperature

  1. Jun 18, 2015 #1

    I have been given an assignment at school to look at various ways heat is transferred through liquids. I'm interested in looking more into the kinetic energy of molecules and how their vibration causes heat, I would like to know if there is a device I could use to record the frequency of molecules in a glass of water, so I could plot molecule frequency vs temperature?


    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Jun 18, 2015 #2


    User Avatar
    Homework Helper

    Maybe you can connect masspieces together with springs
    and investigate the propagation of their oscillations through
    the system? That will simulate the transmission of heat through
    a solid and not a liquid though.
  4. Jun 18, 2015 #3


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    The vibration is heat not the cause of heat.

    If I remember correctly the average velocity of a molecule of water is in the order of 100's of meter per second.
  5. Jun 18, 2015 #4


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    Not sure what you mean by frequency here. Do you mean the proportion of molecules within a given energy band, or the speeds of the molecules?
    You can get an indication of the speeds of the molecules by observing how fast a dye diffuses through the water. But quantifying this is quite advanced physics. See Brownian motion. You could certainly plot diffusion rate against temperature.
    To get an idea of the distribution of speeds, maybe you could measure how well a low-power but finely tuned microwave is blocked by the water. The band of wavelengths blocked widens as the temperature rises because of the Doppler effect. Again, this sounds much too advanced for your purposes.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted