PURPOSE: To illustrate the geometrical effect of free fall.
DESCRIPTION: Two ropes of equal length have steel balls tied at five points along their length. One rope has the balls at equal distances along the rope, while the second has balls positioned geometrically, at distances proportional to the squares of integers: 1, 4, 9, 16, and 25. When the first rope is dropped the equally spaced balls hit the floor at progressively shorter time intervals; when the second rope is dropped, the geometrically positioned balls hit the floor at equal time intervals.
SUGGESTIONS: Drop balls on wooden sounding board to amplify the sound.
REFERENCES: (PIRA 1C20.20)
EQUIPMENT: Two nylon ropes with attached steel balls, as photographed.
SETUP TIME: None.
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