Physics

The comparisons of any physical quantity with a certain basic [arbitrarily chosen, internationally accepted] reference standard

Basic [arbitrarily chosen, internationally accepted] reference standard. The RESULT of a measurement is expressed by a number followed by a Unit ---》 50 cm or 10 kg

1. Fundamental / Basic Units. 2. Derived Units

the unites for the fundamental of BASE qualities. E.G. length - m , time - s , mass - kg

the units derived from fundamental units. E.G. velocity - m/s , acceleration - m/s2

1. CGS system- (cm, g, s) 2. FPS system - (Foot, Pound, Seconds) 3. MKS system - (m, kg, s) 4. S.I. unit -- International System of Units ( 'Systeme Internationale d'Unites')

length, mass , time

There are Seven of them : Length (m) , Mass (kg) , Time (s), Electric Current (A) , Temperature (K) , Amount of substance (mol) , Luminous Intensity (cd)

1. Plane Angle (radian) 2. Solid Angle (Steradian)