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A Earth spin measuring device

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  1. Aug 10, 2016 #1
    Hi

    is there any device or experiment, which could measure earth spin vector and magnitude, centrifugal/centripetal forces, so i could derive from it, where is west and east , whats the vector of earth rotation and whats my lattitude.

    Im assuming these forces and effects has to be measurable with todays technology.

    the device will be stationary, non moving( car, aeroplane), without external referencing, celestial objects,etc...

    spin.jpg
     
    Last edited: Aug 10, 2016
  2. jcsd
  3. Aug 10, 2016 #2

    Tom.G

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    Gyroscope.
     
  4. Aug 10, 2016 #3

    russ_watters

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    Trouble with a gyroscope is it needs to be set up and aligned, so i dont think it can measure the eart's rotation axis.

    My choice would be a sextant, measuring the elevation of Polaris (and with more complex calcs, you can get closer than a half degree).

    For the period....a clock is all you need, and a view of the horizon.

    For forces, that is a lot tougher since gravity and the rotational forces overlap. I'm not sure there is a way to distinguish them in measurements(unless you own a satellite); only in calculations.
     
  5. Aug 10, 2016 #4

    Bystander

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    Pendulum?
     
  6. Aug 10, 2016 #5

    i tried with precision gyroscope, did not work,did not move, i guess too much internal friction in joints
     
  7. Aug 10, 2016 #6
    I meant device without referencing celestial objects, just blindly measuring forces and vectors ( inside the box)

    gravity and the rotational forces overlap, thats true but on poles rotational forces should be zero and at equator should be max, so has to be measurable difference there, from which lattitude could be derived
     
  8. Aug 10, 2016 #7

    russ_watters

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    A gyroscope measures what happens when you move.
    Other than a pendulum to measure the rotation rate, I don't think what you are after can be done.
    That would only be true if the gravitational component of the force were constant, which it isn't.
     
  9. Aug 10, 2016 #8
    yes groscope disk should change angle relative to base, since gyroscope base is moving with earth, but no angle change for me

    gyr.gif
     
    Last edited: Aug 10, 2016
  10. Aug 10, 2016 #9

    russ_watters

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    How far did you move?
     
  11. Aug 10, 2016 #10
    once spun to max revolutions, it took 27 minutes for the disk to stop, i know it needs high rpm all the time, but should move at least few degrees

    7.5 degress in 30 minutes, if all was by the book
     
  12. Aug 10, 2016 #11

    russ_watters

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    What direction was the axis pointed?
     
  13. Aug 10, 2016 #12
    of course i tried all possible angles and orientations, nothing happend
     
  14. Aug 10, 2016 #13

    Dale

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    You can use a Foucault pendulum to measure your latitude.

    A ring laser interferometer will be more reliable than a gyroscope, particularly since it sounds like your gimbal has sticky bearings.
     
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