e/m Apparatus
Perform accurate measurements of the charge-to-mass ratio of the electron. Includes power supplies which can also be used in other experiments.
In 1897, J. J. Thomson showed that the mysterious cathode rays were actually negatively charged particles—he had discovered the electron. In the same year he measured the charge-to-mass ratio of the electron, providing the first measurement of one of the fundamental constants of the universe.
The Charge-to-Mass Ratio System reproduces one version of Thomson’s landmark experiment, providing an accurate measurement of the charge-to-mass ratio of the electron. And, since the electron tube can be rotated through 90°, students can also make a more general study of the behavior of electrons in a magnetic field.
This apparatus also has deflection plates, so students can study the effect of an electric field on moving electrons.