Faraday Cup

A Faraday cup is a metal (conductive) cup designed to catch charged particles in vacuum. The resulting current can be measured and used to determine the number of ions or electrons hitting the cup. The Faraday cup is named after Michael Faraday who first theorized ions around 1830.

Read more about Faraday Cup:  How It Works, Error Sources

Famous quotes containing the word cup:

    In poorer lands
    No one touches the water of life.
    It has no taste
    And though it refreshes absolutely
    It is a cup that must also pass
    Until everybody
    Gets some advantage....
    John Ashbery (b. 1927)