Mass Spectrometry: a practical, hands-on analogy

A practical experiment that I used as a class demonstration, that involves simple lab equipment. By rolling balls down a slope you can symbolize atom acceleration, and by placing a hair dryer perpendicular to the slope, you can symbolize the force of the magnetic field. When the balls roll down they are caught in the stream of air. This shows that atoms with different masses are affected in different amounts by the magnetic field in a mass spectrometer.