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Elastic and anelastic shocks
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Beginning in the eighteenth century, many apparatuses were invented to study the phenomena of elastic and anelastic shocks. Willem Jacob 's Gravesande, Petrus van Musschenbroek, and Jean-Antoine Nollet devised sophisticated and spectacular machines, which they described in their popular treatises on experimental physics.

Nollet's apparatus comprises a large frame topped by a set of rods. From these, a series of wooden and ivory spheres are suspended by pairs of strings. A plumb line ensures the verticality of the device.

One of the classic experiments that can be performed with this apparatus concerns the transmission of an impulse. A ball dropped from a given height along the arc of a circle hits the row of elastic balls. Because the balls are made of ivory, an elastic material, the impulse travels through the entire row of balls, which remain immobile; only the last ball is projected upward. When it drops back, it generates the same phenomenon in the opposite direction.

We can conduct other experiments by changing the number of balls, by attaching balls with different masses to the two-string suspensions, or by changing the arc of the fall, whose opening can be measured by means of rulers fitted on the base of the device.

To study anelastic shocks, the ivory balls are replaced by moist clay balls, which, when hit, are easily deformed.

Objects
Apparatus to study the composition of elastic shocks

Apparatus to study the composition of elastic shocks

Inv. 971
Maker unknown, second half 18th cent.

Elastic and inelastic collisions apparatus

Elastic and inelastic collisions apparatus

Inv. 981
Maker unknown, second half 18th cent.