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How fast am I going?

  1. Jun 24, 2004 #1
    If the planet is moving, the solar system is moving, and the galaxy is spinning, while moving, What's a ruff speed of a person?

    though, lets say im moving that way ---> at 100 mph. i then start to orbit with a diamiter of 100 meters, i cant see this happening with out my speed changing, other wise from a birds eye view i'd just be going left and right while going --->


    on the B part, would i be slowing down?
    on the A part, would i be speeding up?

    I'm guessing no, since there has to be something like drag to slow you down and something to add force to speed you up. but how would that work?
  2. jcsd
  3. Jun 24, 2004 #2
    Everything is moving with respect to something else and the idea that out of the infinite possibilities of motion (speed and directions), one of these things must not moving, there must be a point of rest to refer motion to.

    Mach principle implied that in a completely empty universe, no motion can be detected. This motion is the absolute acceleration while relative velocity can always be defined.
  4. Jun 25, 2004 #3
    .......what? o_O
  5. Jun 25, 2004 #4
    I think I need to analyze your graphic picture. There are two types of motion in your picture. 1. angular motion (rotational), 2. linear motion. The closest analogy that I can think of is the physics of throwing a baseball (curved balls and fast balls).

    For a curved ball, the angular component of the motion must be added to the linear component.

    For a fast ball, the angular component is almost negligible.
  6. Jun 25, 2004 #5
    why not answer the question honestly? whe know that beyond the glactic scale that we are essentially at-rest with the universe's voides expanding between the relatively motionless/drifting galaxies- so all of our motion can be totally expressed by using the galactic core as the reference-

    then you can just look at how we are moving in the galaxy: we are orbiting the center at about 800,000 km/hr- this is most of our motion- we are also orbiting the sun at about 100,000 km/hr- and rotating on the surface of the earth at about 1600 km/hr-

    so you can imagine a tiny spiral within a larger spiral all moving in a giant galactic orbit at about 800,000 km/hr


    /:set\AI transmedia laboratories

  7. Jun 25, 2004 #6


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    Gara, You want to know our absolute speed? Then you have to believe in absolute space. This is not consistent with our current understanding of the universe.

    Consider: while driving in a car, the speed relative to the road is vital, since many things depend on it, not the least of which is the trauma caused by a collision. The speed setAI calculates is of what utility? Newton believed in absolute space, so such a speed was expected to have physical effects. One can try to measure the effect of the luminiferous ether moving through one's body at these tremendous speeds. But if there is no ether, who cares?
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