You can edit almost every page by Creating an account and confirming your email.

Primary instrument

From EverybodyWiki Bios & Wiki

A primary instrument is a scientific instrument, which by its physical characteristics is accurate and is not calibrated against anything else. A primary instrument must be able to be exactly duplicated anywhere, anytime with identical results.

Example

  • Pressure. A U tube filled with water is a primary instrument as the water column differential is unchangeable as water is a basic physical substance. It is accurate due to its nature. Similarly a liquid in glass thermometer is a primary instrument as temperature change causes change in height of mercury column differential of which is unchangeable.

Secondary instruments

Secondary instruments must be calibrated against a primary standard. For example:

  • a dial bourdon tube type pressure gauge must be calibrated against a water or mercury U tube to assure good accuracy.
  • Time. The earth moving in its orbit is primary. Clocks must be calibrated against it.



This article "Primary instrument" is from Wikipedia. The list of its authors can be seen in its historical and/or the page Edithistory:Primary instrument. Articles copied from Draft Namespace on Wikipedia could be seen on the Draft Namespace of Wikipedia and not main one.