Simple Cavendish Experiment Model

This is a very simple model of the Cavendish Experiment, performed in 18thC England by Henry Cavendish. The premise is that the attraction between the larger and smaller balls causes the balance bar to sway in a small but measurable fashion, making it possible to measure the force of gravitational attraction and the gravitational constant.

If someone wanted to make a higher fidelity model, I would focus on making a true torsion wire (that freely spins) holding up the balance bar. I also used 1 inch and 1/4 inch bearings for the balls (ie a 4:1 size ratio) because that was what I had on-hand. The actual experiment used balls with a 6:1 ratio.