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Category Videos
Not Right For WatchKnowLearn
Ages: 14 - 18
Basics of Astronomy: Time
From YouTube, produced by Kurdistan Planetarium
Ths video, using simple computer animation, offers information on how humans perceive time. (02:45)
Found by teresahopson in Time
August 13, 2011 at 02:19 PM
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Not Right For WatchKnowLearn
Ages: 13 - 18
The History of Keeping Time
From ted.com, produced by TED education
Where did time-telling come from? What are time zones and why are there so many of them? Get the answers to these questions and more in this journey through the history of time -- from sundials to hourglasses to modern clocks.  (03:47)
December 26, 2012 at 03:32 PM
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Not Right For WatchKnowLearn
Ages: 14 - 18
Discovery - First Time Machine
From YouTube, produced by Discovery Science
What does a cup of coffee have to do with the speed of light? Watch this clip taken from the Discovery Channel documentary 'The First Time Machine' (05:31) to find out.
Found by teresahopson in Time
May 29, 2010 at 05:33 PM
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Not Right For WatchKnowLearn
Ages: 10 - 18
Why Some Days Aren’t 24 Hours
From YouTube, produced by minutephysics
This video is about the length of a solar day vs a stellar day vs a mean standard day, what they all have to do with each other and the earth's orbit, eccentricity, axial tilt, and so on. Also, aliens and asteroids. It'll explain the equation of time... [more]
Found by andrewvanzyl in Time
August 27, 2019 at 08:27 AM
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