Helena Antonaccio (born March 21, 1949 in Morristown, New Jersey) was Playboy magazine's Playmate of the Month for the June 1969 issue.
Here she demonstrates conservation of momentum and energy...
In 1967 English actor Simon Prebble coined the name 'Newton's Cradle' (now used generically) for a version of the device that demonstrates conservation of momentum and energy, manufactured by his company, Scientific Demonstrations Ltd . Harrods of London stocked the model, effectively creating the executive toy market.