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09-25 How Do We Test?

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    Now, maybe you don't believe me, maybe you don't believe that
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    special relativity could possibly be for real.
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    Clock's disagreeing with each other--what's going on, how do we test it.
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    Well, as a matter of fact, we're actually testing special relativity right now,
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    and we're doing that with a series of GPS satellites which are constantly in orbit over earth.
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    The way these satellites can localized someone's position on earth so precisely involves
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    precised measurements of distance between each satellite and the observers' GPS device.
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    This precised distance measurements actually require a precised time measurements,
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    but these satellites are moving relative to the earth, relative to the observer.
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    In fact, they're traveling at about 14,000 km/h.
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    Can you tell me what β is associated with 14,000 km/h--
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    a.k.a. what fraction of the speed of light is this.
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    Enter your answer in scientific notation.
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    I've put the 10 in here for you and you can put the exponent in here and the rest can go right here.
タイトル:
09-25 How Do We Test?
Video Language:
English
Team:
Udacity
プロジェクト:
PH100 - Intro to Physics
Duration:
0:57
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English subtitles

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