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Energy Defined
2m 41s
What is energy and why are we on a never ending search for new energy sources?
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Video description: Why does the nose of the football go from pointing upward to rotating downward when most things stay the same orientation when they move through the air? (Think of frisbees, bean bags, even paper airplanes.) The reason is something called "conservation of angular momentum." Discover the physics that explains how a perfect football pass moves through the air.