ANDREW BROOKES, NATIONAL PHYSICAL LABORATORY / SCIENCE PHOTO LIBRARY ANDREW BROOKES, NATIONAL PHYSICAL LABORATORY / SCIENCE PHOTO LIBRARY
Primary low force balance. This machine measures very small forces using electrical and dimensional analysis to establish the primary standard for forces of 10 micronewtons (millionth of a newton) or less. The balance measures from 10 micronewtons to 1 nanonewton (billionth of a newton), with a resolution of 50 piconewtons (trillionth of a newton). It produces the most accurate measurement of minute forces to date (as of 2007). Previously, these forces had been measured using the weight of their mass in a gravitational field, Masses under 1 milligram, however, are too small to be measured accurately this way, so the primary low force balance was introduced to solve this flaw. Photographed at the National Physical Laboratory in Teddington, UK.
Model release not required. Property release not required.