Question asked by Filo student

hyperfine levels of the ground state of the cesium-133 atom. (1967)

1. The ampere is that constant current which, if maintained in two straight parallel conductors of infinite length, of negligible circular cross-section, and placed 1 metre apart in vacuum, would produce between these conductors a force equal to $2\times 10^{-7}$ newton per metre of length. (1948)
2. The kelvin, is the fraction $1/273.16$ of the thermodynamic temperature of the triple point of water. (1967)
3. The mole is the amount of substance of a system, which contains as many elementary entilies as there are atoms in $0.012$ kilogram of carbon - 12. (1971)
4. The candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency $540\times 10^{12}$ hertz and that has a radiant intensity in that direction of $1/683$ watt per steradian. (1979)

Views: 5,505 students

Updated on: Dec 30, 2022