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"Suppose a cannon ball, tied with a string to the centre of a slab of smooth marble, and suppose an attempt be made to push this ball with the hand in the direction of b; it is obvious that the string would prevent its going to that point; but would keep it in thei circle. n this case, the string is the centripedal force." -Comstock 1850

Centrifugal Force

"Suppose a cannon ball, tied with a string to the centre of a slab of smooth marble, and suppose an…