Science and Mathematics Initiative for Learning Enhancement (SMILE)
Smile: Measuring the Gravitational Constant, G
A demonstration/lab idea for determining the numerical value of the universal gravitation constant using a torsion balance.
Wikimedia
Wikipedia: Henry Cavendish
Wikipedia offers biographical information on the British scientist Henry Cavendish (1731-1810), credited with having discovered hydrogen, which he described as "inflammable air."
National High Magnetic Field Laboratory
Magnet Academy: Torsion Balance
Experiment with the torsion balance and see what happens first by giving the rod a charge, and then by moving the charged rod closer to the outer metal sphere of the instrument. Observe what happens to the needle as the charge increases.
National High Magnetic Field Laboratory
Magnet Academy: Torsion Balance 1785
Read about Charles Augustin de Coulomb, who didn't invent the torsion balance, but was the first to discover it could be used to measure electrical charge- the first device capable of such a feat.
National High Magnetic Field Laboratory
Magnet Academy: Charles Augustin De Coulomb
Charles-Augustin de Coulomb invented a device, dubbed the torsion balance, that allowed him to measure very small charges and experimentally estimate the force of attraction or repulsion between two charged bodies. The data he obtained...
Physics Classroom
The Physics Classroom: Cavendish and the Value of G
A short description of how Cavendish measured the value of G - the universal gravitation constant and supported Newton's theory. Illustrated.