The Brazil nut effectI keep a tin of mixed nuts in the kitchen from which I pick a few a day to snack on, as a means of ensuring that I eat some good fibre every day. And it is always curious why the heaviest Brazil nuts always appear at the top of the tin. This is a gravity-defying phenomenon I think my dog would have found interesting, and as usual, he would be right, because there are several important scientific implications derived from this ‘Brazil Nut Effect’.
For a considerable period of time, scientists have struggled to explain why larger and often heavier particles in a mixture tend to rise to the top when agitated. The phenomenon, officially known as granular convection, occurs not just with nuts, but in cereal boxes, on riverbeds, and even on the surfaces of asteroids.
