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In support of all the students who are displaced from school due to the Corona virus. Access to physics zone and chemistry zone lessons are now available free of charge. This will be maintained at least through August 1st 2020. Learn and be well.

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Proof of the Cliff Drop

In physics it is usually not safe to accept a computer simulation until after it is tested in reality.  This movie is of two ball bearings that are simultaneously dropped and horizontally thrown.  It is a movie of real life, not a simulation. 


[animated gif version]

The pink highlighted circles are only to draw your attention to the hard to see ball bearings.  You will notice that the ball bearings don't quite appear to be level with each other.  It is an optical illusion caused by the projectile bearing on the left being shot slightly toward the camera.  You will notice that they are in fact level because they both hit the floor at the same time.  Also notice that even the second bounce of two ball bearings are simultaneous.

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