Hallwachs's electroscope

Hallwachs's electroscope

H305/0213 Rights Managed

Request low-res file

530 pixels on longest edge, unwatermarked

Request/Download high-res file

Uncompressed file size: 42.9MB

Downloadable file size: 1.8MB

Price image Pricing

Please login to use the price calculator


Caption: Hallwachs's electroscope. This device was used in an 1888 experiment by the German physicist Wilhelm Hallwachs (1859-1922), the results of which were explained by J. J. Thomson. Light passing through the square hole in the black plate illuminates a round copper plate. Below this is an electroscope (cylinder) that is negatively charged (as seen by the thread attracted to one side). If the light is of sufficient energy, the electroscope will lose its charge (the thread falls). Thomson explained this as light causing electrons to be emitted from the copper plate, to be replaced by charge from the electroscope. Einstein, in 1905, used quantum theory to explain this photoelectric effect, and this won him the 1921 Nobel Prize for Physics.

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

Keywords: aether, device, einstein, electric charge, electroscope, equipment, ether, experiment, experimenting, hallwachs's, instrument, invariant, laboratory, one, photoelectric effect, physical, physics, quantum physics, relativity, research, single, special relativity, speed of light, wilhelm hallwachs

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