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  • sotongeoffsotongeoff Posts: 9,802

    Don't know the answer to that one Caz-but will find outimage-now how about this?~~

    If you hover in a helicopter over the Earth-and the Earth is spinning -can you just wait for the countries you want to visit to come round so you can land on them?

  • Caz WCaz W Posts: 1,353

    Think of the other things they do in the water too Deanimage

  • Why is milk white when it comes from a cow, who's stable diet is grass which is green?

  • Caz! image

  • Geoff! imageimageimage

  • sotongeoffsotongeoff Posts: 9,802

    This is what I thinkimage

    Because of relativity, to you the observer, your headlights work exactly the same no matter your speed These are exactly the kind of question that Einstein often asked himself from the age of 16 until he discovered special relativity ten years later. Einstein reported that in 1896 he thought,

    ``If I pursue a beam of light with the velocity c (velocity of light in a vacuum), I should observe such a beam of light as a spatially oscillatory electromagnetic field at rest. However, there seems to be no such thing, whether on the basis of experience or according to Maxwell's equations. From the very beginning it appeared to me intuitively clear that, judged from the standpoint of such an observer, everything would have to happen according to the same laws as for an observer who, relative to the earth, was at rest. For how, otherwise, should the first observer know, i.e., be able to determine, that he is in a state of fast uniform motion? One sees that in this paradox the germ of the special relativity theory is already contained. Today everyone knows, of course, that all attempts to clarify this paradox satisfactorily were condemned to failure as long as the axiom of the absolute character of time, viz., of a simultaneous, unrecognizedly was anchored in the unconscious. Clearly to recognize this axiom and its arbitrary character really implies already the solution to the problem.''

    In 1905 he realised how it could be that light always goes at the same speed no matter how fast you go. Events that are simultaneous in one reference frame will happen at different times in another that has a velocity relative to the first. Space and time cannot be taken as absolute. On this basis Einstein constructed the theory of special relativity, which has since been well confirmed by experiment.

    If you want to know what happens when you are driving at very nearly the speed of light, an answer can be given. Within your car you observe no unusual effects. You can look at yourself in your mirror which is moving with the car and you will look the same as usual. Looking out of the window is a different matter. The light from your headlights will always go at the speed of light in your reference frame. It will strike any object in its path and be reflected back. Everything else will be coming towards you at nearly the speed of light, so the light reflected from it will be Doppler shifted to very high frequencies--towards the ultraviolet or beyond. If you have a suitable camera you could take a snapshot. The objects passing are contracted in length but because of the different times of passage for the light and effects of aberration, the snapshot will show the objects you pass as rotated

    imageimageimage

  • Caz WCaz W Posts: 1,353

    Well, that's as clear as mud - thanks Geoff image  I thought it was something to do with thatimage

    Have you ever imagined a world with no hypothetical situations?

  • Caz! There ya go! All is now clear! image

  • sotongeoffsotongeoff Posts: 9,802

    Still want an answer to my helicopter question.

  • Geoff! It has to be true in my eyes! If you hover n it spins! Surley! image

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