Is it required to learn these definitions of base units?
Is it required to learn these definitions of base units? mlandty
Sr Base gunntitles and Units*
metre is the length of the path trHve11ed bv light In vacuum
during a time interval of of a second. (1983)
me kilogram Is equal to the mass of the tnt«natlonal prototype
of the kilogram (H plHtinum-ifidt11m alloy cylinder) kept at
international Bureau of Weights and Measures, at Sevres, near
Paris. France. ( 1889)
The second Ls the duration of g, 192,631,770 periods of the
radiation corresponding to the transition Ext'.veen the two
hyperfine levels or Lhe ground sLaLe of the cesium-133 alum.
me ampere is that constant current which, if maintained in
two straight parallel conductors of Inftnlte length. ofnegllglble
circular cross-section, and placed 1 metre apHrt in vacuum,
would produce between these conductors a equal to & 1 (Y'
newton 11teLre of length. [1948)
The kehhn. is the fraction 1/273.16 of the thermodynamic
temperature of the tliple point of water. (1967)
The mole is the amount of of a system, which contains
as many elementary- entities as there alæ atoms in 0.012
kllogram of carbon - 12. (1971)
'Ihe candela is the Luminous intensity, in a *ven
direction, of a source that eliliLs Inunuchrunalic radiaüun of
frequfflcy 540x1012 hertz and that has a radtant Lntenstty tn
that direction of 1/683 watt per steradian. ( 1979)
The values mentioned here need not be remembered or asked in a test. Tzey are given here only to indicate the
These are the fundamental definitions of the base units, only knowing the physical quantity and there units are not enough for a science student, so you should know the basic definitions of the base units.