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SWITCH PITCH BALL Spotted with BILL GATES
Switch Pitch Ball: this spherical assembly changes color by turning inside out when tossed into the air. Advertisements for this toy incorrectly claim air drag is involved in the transformation. The ball is made of multiple components hinged together. In launching the ball from the hand an upward acceleration results in a torque that pivots each component around its center of mass, causing the rotation of these components in an organized way leading to the transformation. Imagine tossing a stick straight up. If the stick is perfectly vertical upon launch it will move straight up- but if it is initially slanted at all it will also begin to rotate upon launch. Similar physics underlies the motion of each component of the ball- shown here in 240 fps slow motion. The Switch Pitch is produced by the makers of the Hoberman Sphere.