Description

This simulation illustrates Galileo's experiments with inclined planes. Galileo rolled balls down gently sloped planes in order to observer how the distance of travel increased with time. He did not have accurate clocks so he instead placed frets along the plane and when the ball would roll over the fret it would make a sound (without significantly slowing the ball down). By moving the frets around Galileo was able to place them such that the sound of the ball hitting the frets produced a regular beat (Galileo was musically trained and had an excellent sense of rhythm). Using this technique he was able to show that the balls rolled down the plane with constant acceleration.

The main window shows a red ball on a brown inclined plane. A red marker indicates the starting point and moveable black markers show the positions of the frets. When the ball passes a fret the color of the plane changes. The frets can be moved so that these color changes occur on a regular beat, indicating the the ball moves between frets in equal time intervals. The distances of the frets from the starting point can be measured with a ruler that is built into the simulation.

Controls allow the user to change the angle of inclination for the plane and the initial speed of the ball. The user can choose to display the ruler and a clock to show elapsed time, the frets. The user can diable the frets as well as plots of position and velocity versus time. Finally, the user can turn air resistance on or off (the background turns blue when air is on).