It isn’t certain when the Newton’s Cradle was actually invented, but it was probably in the late 1960’s. Whilst named after Sir Isaac Newton, he certainly had nothing to do with its actual creation, other than through discovering gravity and his work on understanding the laws of physics of course.
The Newton’s Cradle was the invention that really started the idea of the “Executive Toy”, something that someone in a high position in a business wouldn’t be afraid to have on their desk as an idle distraction from their busy work schedule. Nowadays there are a whole range of such gizmos, but it was only in the Eighties, with the rise of the Yuppie and their disposable income that such trivialities became really popular.
So what is a Newton’s Cradle. Put simply it is little more than five balls suspended from a frame, but it is also a great tool for explaining gravity, pendulum motion and the principal of conservation of energy and momentum. Pulling one of the balls aside and letting it drop into the others transfers all it’s energy through the remaining balls onto the last one, which then swings up into the air, only to drop down and repeat.
In a perfect world, with no friction or air resistance the Newton’s Cradle should go on doing this nearly forever, but of course in the real world it will slowly come to a halt as the amount of energy in the system gradually lessens fighting against all these other physical barriers, as well as producing that clacking sound as the balls collide with each other.
The first Newton’s Cradles were very expensive, being precision made from wood. They were sold in a high end shops such as Harrods, but as time went by the toy evolved into the classic design we know today, with the balls and frame being made from metal and the supporting wires becoming pieces of thin cord or plastic.