DAY 2- FUNDAMENTAL UNITS

Question 1

Length (m)

Answer 1

length of parh travelled by light in a vacuum during a time interval of 1/299 792 458

Question 2

Mass (kg)

Answer 2

equal to the mass of the international prototype kilogram (IPK) which is a platinum (90%) Iridium (10%) allow cylinder with a height and diametee of 39.17 mm

Question 3

Time (second)

Answer 3

duration of 9 192 631 770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the Cs-133 atom

Question 4

Mole

Answer 4

amount of substance of a system which contains as many elementary entities as there are atoms in 0.012 kg of C-12 atom

Question 5

Kelvin

Answer 5

Fraction 1/273.16 of the thermodynamic temp of the triple point of water havinf the isotopic composition 0.00015576 mole or 2H per mole or 1H, 0.0003799 mole or 17O per mole of 16O and 0.0020052 mole of 18O per mole of 16O

Question 6

Electric Current (Ampere)

Answer 6

constant current on negligible circular cross section and placed 1 m apart in vacuum would produce between these conductors a force equal to 2x10^-7 Nm^-1

Question 7

Candela (luminous intensity)

Answer 7

luminous intensity of a source that emits monochromatic radiation of frequency 540 x10^12 herts and that has a radiant intensity in that direction of 1/683 watt per steradian