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What happens to the missing time?

  1. Jun 11, 2012 #1
    What happens to the missing time??

    It has been observed that the earth's rotational period to be roughly 23 hours and 56 minutes.But the clocks we use indicate 24 hours. So there should be a difference of 4 minutes for each day. Could somebody please explain what happens to this additional 4 minutes?
  2. jcsd
  3. Jun 11, 2012 #2
    Re: What happens to the missing time??

    Since the Earth is also revolving around the Sun (in addition to rotating), it needs to turn slightly more than one full rotation in order for the Sun to be in the same apparent position in the sky from day to day. This difference is approximately four minutes.

    (And of course, we account for the "approximate" nature with leap days, leap seconds, etc...)

    The animation here is a bit slow, but helps visualize:
    Last edited: Jun 11, 2012
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