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Physics of movement

  1. Aug 17, 2006 #1
    The earth spins on it's axis at approximately 2 mi/sec(795 mi/hr), it
    spins around the sun at approximately 18.5 mi/sec(67,000 mi/hr), and
    the sun along with all of the planets spins around the center of the
    galaxy at 144 mi/sec(1/10th the speed of light. So how come we don't
    feel all of that motion?
  2. jcsd
  3. Aug 17, 2006 #2


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    We don't sense velocity with our bodies, only change in velocity.
  4. Aug 24, 2006 #3
    The speed of light is 186,282 mi/sec, and 144 mi/sec is nowhere near 1/10th of that.
  5. Aug 25, 2006 #4


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    example...flying in an airplane. You don't feel the motion while traveling at a few hundred miles per hour (turbulence aside) but you do feel the change in velocity (acceleration) when taking off.
  6. Aug 25, 2006 #5


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    Suppose you were blindfolded and sat in a chair at the north pole. In 24 hours you would turn through 360 degrees, in one hour through 15 degrees. Do you suppose that without some exterior visual cue you could "feel" that speed of rotation? And everywhere else than the poles, the experienced earthly rotation is less; at the equator it's zero - parallel transport! And all the other rotation speeds you cite are less than the earth's, 360 degrees in a year? 360 degrees in umpty billion years? Man when you turn your head to one side you do 90 degrees in half a second; that's 648,000 degrees per hour, for comparison.
  7. Aug 30, 2006 #6
    can this be considered as an example for inertia?
  8. Aug 30, 2006 #7


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    Plus the atmosphere spins at pretty much the same rate as the Earth, that helps in not feeling anything... :smile:
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