Definition of spectrometer. 1  1 : an instrument used for measuring wavelengths of light spectra. 2  2 : any of various analytical instruments in which an emission (as of particles or radiation) is dispersed according to some property (as mass or energy) of the emission and the amount of dispersion is measured nuclear magnetic resonance spectrometer.
1 bar is equal to 1000 millibars. Just like how there are 1000 millilitres in a litre, and 1000 milliseconds in a second. 1 millibar = 0.001 bars.
The use of millibars is slowly giving way to the equivalent. SI unit of hectoPascals (hPa). The mean atmospheric pressure at. sea level is given equivalently as P = 1.013x105 Pa = 1013 hPa =. 1013 mb = 1 atm = 760 torr.