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Instructional Video12:55
Crash Course

Why We Can't Invent a Perfect Engine: Crash Course Engineering #10

9th - 12th Standards
Your car's engine is likely to be only 20 percent thermally efficient. Why so inefficient? Viewers of the 10th video in an engineering series learn how the second law of thermodynamics and entropy limit the efficiency of a car engine....
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Instructional Video4:32
TED-Ed

The Chemistry of Cold Packs

7th - 12th Standards
How can it take water hours to freeze, but a cold pack can go from room temperature to near freezing in an matter of moments? Find out with this short video that explores the endothermic reaction that make these modern marvels possible.
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Instructional Video5:39
Be Smart

The Amazing Science of… DUST?

6th - 12th
Why do we bother to dust when more will start to land as soon as we get rid of it? What is dust made of and why won't it ever go away? The video answers these questions and more. 
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Instructional Video5:34
TED-Ed

At What Moment Are You Dead?

7th - 12th Standards
When is a person no longer living? This question has been puzzled over for millennia, but is there a clear answer? Watch as this video examines the biological line separating life and death.