Board of Trade current balance, 1950

Board of Trade current balance, 1950

V510/0068 Rights Managed

Request low-res file

530 pixels on longest edge, unwatermarked

Request/Download high-res file

Uncompressed file size: 52.1MB

Downloadable file size: 1.5MB

Price image Pricing

Please login to use the price calculator


Credit: NATIONAL PHYSICAL LABORATORY (c) CROWN COPYRIGHT/SCIENCE PHOTO LIBRARY

Caption: Board of Trade current balance. This current balance is also known as an ampere balance or Kelvin balance. It is an electromechanical apparatus used for the precise measurement of the ampere, a unit of electric current. The current to be measured is passed through two coils (seen around a marble cylinder at lower left) and the magnetic force between the two coils is measured to give the magnitude of the current. The current balance was invented by William Thomson, the First Baron Kelvin, in 1882. Photographed in 1950.

Release details: Model release not required. Property release not required.

Keywords: 1900s, 1950, 1950s, 20th century, ampere, ampere balance, analysing, analysis, balancing, black-and-white, board of trade, coils, current, current balance, cylinder, electrical, electricity, england, english, equipment, historical, history, history of science, kelvin balance, machine, measuring, meter, monochrome, national physical laboratory, npl, physical, physics, power, scales, technological, technology, test, testing

Licence fees: A licence fee will be charged for any media (low or high resolution) used in your project.