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To: Ingtar

If you had a powerful enough laser pointer, and a big enough screen at a good distance away from you... would moving a spot on the screen by rotating the laser pointer fast enough, give a tangential speed of the spot greater than the velocity of light, in vacuum? Point to ponder :)


14 posted on 11/21/2008 6:54:51 PM PST by MyTwoCopperCoins
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To: MyTwoCopperCoins

Kind of like the intersecting point of scissors. The intersection point doesn’t have a speed limit because it has no mass.


18 posted on 11/21/2008 6:58:11 PM PST by cripplecreek (The poor bastards have us surrounded.)
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To: MyTwoCopperCoins
Spot = image, images can more faster than light. An oscilloscope sweep line can move faster than the speed of light.
24 posted on 11/21/2008 7:08:00 PM PST by The Cajun (Mind numbed robot , ditto-head, Hannitized, Levinite)
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To: MyTwoCopperCoins

None of the photons are moving faster than the speed of light. Only the image in your brain suggests that, but there is no one thing out there breaking any physical laws.


27 posted on 11/21/2008 7:11:52 PM PST by steve86 (Acerbic by nature, not nurture™)
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To: MyTwoCopperCoins

Thick as I am I can answer that ponderous point.

The dot only appears to move so answer is no.


28 posted on 11/21/2008 7:15:14 PM PST by count-your-change (You don't have be brilliant, not being stupid is enough.)
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To: MyTwoCopperCoins
If you had a powerful enough laser pointer, and a big enough screen at a good distance away from you... would moving a spot on the screen by rotating the laser pointer fast enough, give a tangential speed of the spot greater than the velocity of light, in vacuum? Point to ponder :)

The power of the laser really doesn't matter, nor do you need a screen, just aim a laser straight up and press the "on" button. The radial velocity of the beam would be "C". The tangential velocity would be the rotational velocity of the earth in radians per second times the instantaneous radius of the leading edge of the laser beam or "C" times the time interval since the beam was switched on. The vector sum would be (C*C*T)1/2 which looks to me like it's greater then "C" and increasing as a function of "T".

Obviously I'm missing something...

Ah well, Newtonian physics got me through 40 years of engineering, I think I'll quit while I'm still "relatively" sane!

Regards,
GtG

32 posted on 11/21/2008 7:28:11 PM PST by Gandalf_The_Gray (I live in my own little world, I like it 'cuz they know me here.)
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To: MyTwoCopperCoins

It isn’t one photon moving in a circle so who cares? It’s different photons at hitting points widely enough separated that a single photon couldn’t get from one place to the other in the time interval.


33 posted on 11/21/2008 7:31:38 PM PST by Still Thinking (Quis custodiet ipsos custodes?)
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