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Does damping of period affect the period?

  1. Apr 29, 2010 #1
    Hi there,

    Sorry typo in the title and I can't figure out how to change it!
    I am just wondering if anyone can help me - does damping (drag) increase the period of a pendulum? As opposed to if it was in a vacuum?

    I have been trying to figure this out for some time - I know that drag is dependent on the velocity of the period, but does it actually change the period?

    I am giving a presentation on how the period of a physical pendulum increases as the mass distribution changes (centre of mass lowers, the effective length gets longer) and I was once told by a lecturer that damping does not in fact change the period, but I don't see how? Surely it would slow it down, thus increasing the period?

    Would greatly appreciate any thoughts on this!

  2. jcsd
  3. Apr 29, 2010 #2
    In general, over damping and critical damping of the system produce non-periodic motion.
    Under damping will produce a frequency that is less than the natural frequency by an amount that depends on the "damping ratio".
    Plenty of information here
    For air pendulums the amount of damping is very small, resulting in a negligible decrease.
  4. Apr 29, 2010 #3

    Vanadium 50

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    Imagine a pendulum in honey. Will it take longer for it to make a full oscillation?
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