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CD on glass casimir effect ?

  1. Mar 20, 2010 #1
    I know the question sounds a little bit noobish but If you place a CD on a clean glass table seems like the CD is floating. There's vacuum between the CD and the glass stopping you from picking it up yet the CD seems to be floating.
    If not I would like to know what other forces could be acting there.
  2. jcsd
  3. Mar 20, 2010 #2


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    Er... you do know that there's a clear coating on the CD that separates the actual layer from air, don't you?

  4. Mar 20, 2010 #3
    I know (I'm a computer geek).. but how's that relevant to the question ?.. except for the fact that it's a near-perfect plane that could enforce my question.
  5. Mar 20, 2010 #4
    That's just air being caught between the smooth, very flat surfaces. Since the separation is narrow, the air can only escape (or enter) slowly, and the resulting pressure causes it to seem to float (or 'stick'). The air escapes after a few moments and the CD touches the glass.
  6. Mar 20, 2010 #5
    Thanks, I guess I was thinking too far !
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