REDEFINED UNITS OF MEASUREMENT OF KILOGRAM, KELVIN, MOLE AND AMPERE

May 21, 2019

On the occasion of World Meterology Day, the Council of Scientific and Industrial Research and National Physical Laboratory (CSIR-NPL) introduced redefined International System of Units for the country.

About: 

  • The redefined systems are:
    • Kilogram (SI unit of weight),

    • Kelvin (SI unit of temperature),

    • Mole (SI unit of amount of substance), and

    • Ampere (SI unit of current).



  • Timeline:
    • During the open session of the General Conference on Weights and Measures (CGPM) at BIPM in November 2018, the world’s scientific community, adopted the resolution to redefine four of the seven base units

    • The new SI is being implemented worldwide from 20th May 2019 i.e. the World Metrology Day.



  • Significance of decisions:
    • This decision has now enabled scientists to base the SI units entirely on fundamental properties of nature, which will ensure their ongoing refinement and improvement for years to come.

    • The fundamental constants are invariants of time and space and successfully replaced the artifact based units. This will enable world-wide coherence of measurements.

    • It has opened up the new era for quantum world by linking all seven base units to fundamental constants/quantum standards.



Source : PIB