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Does the clock aboard a GPS ... 
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#1
Apr611, 12:57 PM

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sattelite tick slower than an earth bound clock. Lets say an atomic clock.
From what Ive gathered so far, the clock aboard the GPS sattelite ticks slower The sattelite is in free fall so the clock aboard the sattelite is in zero G. Is the zero G condition the only condition that cause the sattelite clock to tick slower? 


#2
Apr611, 01:17 PM

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See the thread http://www.physicsforums.com/showthread.php?t=487230



#3
Apr611, 03:17 PM

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http://www.lightandmatter.com/html_b...ch02/ch02.html
Use your browser's search function to find the text "Let's determine the directions and relative strengths of the two effects in the case of a GPS satellite." 


#4
Apr611, 06:56 PM

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Does the clock aboard a GPS ...



#5
Apr711, 12:24 AM

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#6
Apr711, 07:00 PM

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#7
Apr811, 06:56 AM

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The effect due to gravitational potential is more significant than the velocity effect  GPS clocks are preset before launch to run slower so that in orbit they run approximately synchronous with earth clocks. Without that adjustment they would tick very slightly faster than earth clocks. See the already provided references for details. 


#9
Apr811, 02:26 PM

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So i gather the GPS clocks tick faster than earth bound clocks  any links to reference materials on that. So evidently, zero gravity (free fall) is not the only condition. The current science suggests that there is more than one condition that can effect a clock's timing . If there is more than one condition, are the conditions dependant on each other?
Oh i found the above link  time dialation looks like pretty exotic stuff 


#10
Apr811, 07:21 PM

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#11
Apr811, 07:33 PM

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Imagine a spaceship hovering stationary at a height equal to the GPS satellites. It has the same gravitational effects on its time that the GPS satellites have. However, since it is not moving at a high speed, it does not have the same effects from velocity. 


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Apr811, 08:00 PM

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Apr811, 08:02 PM

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Apr811, 08:27 PM

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Apr811, 08:52 PM

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