Physical Quantities:
This is one way of dividing the physical quantities that we encounter:
Division of physical quantities into fundamental and derived quantities.
And this is the second way of dividing them:
Division of physical quantities in terms of vector and scalar
Unit of length:
-> Definition: “Length of path travelled by light in vaccum during the time interval of 1/299792458 of a second”
-> Some units to measure small distances:
(Note: ^ stands for “to the power of”)
1 micron or micrometer = 10^-6 meters
1 nano meter = 10^-9 meters
1 Angstrom = 10^-10 meters
1 Femto meter = 10^-15 meters
-> Some units to measure large distances:
1 light year = 9.46 x 10^15 meters
Unit of mass:
-> Definition: “Mass of a particular solid cylinder of platinum-iridium kept at Sevres
Unit of time:
-> Definition: “Defined using atomic clock which works on energy changes in gaseous cesium atoms.
