isobar
/ˈʌɪsə(ʊ)bɑː
/noun
1 Meteorology A line on a map connecting points having the same atmospheric pressure at a given time or on average over a given period.Secret Meteorological Office charts show the alarming swirl of isobars converging in black lines over the Channel....
- The tight spacing of the isobars indicates strong northerly winds, averaging some 50 km/h over much of Victoria.
- When isobars on a weather chart are close together, it will be a blustery day…
1.1 Physics A curve or formula representing a physical system at constant pressure.The heating isobar for the transformed monolayers remained virtually superimposable on the curve for films that had experienced no rapid compression....
- No discontinuous change occurs in either the compression isotherm or the heating isobar.
- For the heated film, the substantial reversion of the transformed film to the original behavior occurred without any discontinuous change in area or in the slope of the heating isobar.
2 Chemistry Each of two or more isotopes of different elements, with the same atomic weight.
Derivatives
isobaric
/ adjective ...- A phase transition produced by isothermally increasing surface pressure can often be reversed during isobaric heating.
- This diagram is the same as the one above except that the major pressure and wind zones have been replaced by a typical isobaric weather map.
- For all simulations, isothermal and isobaric conditions were assumed.
Origin
Mid 19th century: from Greek isobaros 'of equal weight', from isos 'equal' + baros 'weight'.