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Can speed of light be faster with this?

  1. Jul 18, 2011 #1
    Can this be doable in theory? Because who in the right mind would build this :)

    Let us imagine if we could build a steel rod, that has mass of 1 Kg, that has length about 300000 km. Yeah I know, impossible, but how about some material that can weight 1Kg or even 10Kg. But in space even 1000 tons of material is like a feather.

    Now let's say that we anchor one side to earth, asteroid or whatever.
    If rod is r in circle, then quarter of circle would be 471000 km.
    Now few cm from anchor we push or pull rod for a 1/4 circle, because there is no resistance in space/universe, or it is minor, it could be pushed or pulled by a second or fraction of a second. So the far end would cross 471000 km by a second or less.
  2. jcsd
  3. Jul 18, 2011 #2
    What do you think happens on a molecular level when you push something?
  4. Jul 18, 2011 #3
    The mass of an object doesn't change by moving it to space, it's weight will change but not it's mass.

    Are you saying that you want to turn this rod in a circle with one end being the center of the circle and the other end being the edge of the circle? I believe that is what you are saying, but it's a little difficult to tell. Anyway, you say there would be little to no resistance to pushing or pulling on this rod. This simply is not true. If you are rotating the rod it has a moment of inertia, which is the resistance to change in rotation. If you are simply moving the rod (not rotating) it has inertia (it's mass) which is a resistance to change in momentum. You will not be able to move this rod faster than the speed of light.
    Last edited: Jul 18, 2011
  5. Jul 18, 2011 #4
    This is completely impossible for the following reasons;

    1. There is no material in existence both that light and strong.
    2. No matter what the mechanism nothing with a rest mass can accelarate to c. There is no tricking relativity here!
  6. Jul 18, 2011 #5


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    I'm afraid you're mixing up http://en.wikipedia.org/wiki/Weight" [Broken]. 1000 tons in space would be just as hard to move as 1000 tons on Earth (well it would be a little easier thanks to the lack of friction).

    Compressive forces don't travel instantly through materials unfortunately, they travel at the speed of sound. When you push an object the first atoms bang into the next, which bang into the next etc. Nothing faster than light here :)
    Last edited by a moderator: May 5, 2017
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