Purpose: To show the surprising effect of an impulse load on a large inertial mass.

Suspend this heavy cast iron ball by one of its eyes using a lightweight cord. Tie another piece of the same cord to the lower eye, then jerk down hard on the bottom cord. Replace the cord that breaks with a fresh cord and pull down on the bottom cord slowly but gently. The results reveal worlds about inertia. The enameled iron sphere comes with two eyes mounted at the opposite ends of a diameter and a third eye for a safety cord to prevent the ball from falling.

There is no specific stand for the demo, one must be made from materials available.

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