Basic Types of Physical Quantities

1. Mass (m) is a basic property of matter. It is the measure of the amount of matter it contains. The standard unit of mass is the kilogram, kg. One kilogram (kg) is the mass of 1 liter (L) of water at 4°C and a pressure of 1 atmosphere (atm). The mass of an object remains the same even if the position of the object is changed with reference to the earth?s center.
2. Length (l) is a distance between two distinct points. It is measured by using a metric ruler. Width (w) is also a length, and height (h), is the vertical distance. The basic unit is the meter (m).
3. Time (t) is the regular interval between two successive points. The standard unit of time is the second. The second was originally defined in terms of the motion of the earth, but it was revised and instead compared to vibrations of cesium atoms.
4. Temperature (T) is the measure of the hotness or coldness of an object. It is technically defined as the measure of the average kinetic energy of a body. Kelvin (K) is used as the basic unit.
5. Electric current (I) is the measure of the flow of electrons or charges. An ammeter is used to measure current expressed as Ampere (A).
6. Luminous intensity (E) is the amount of illumination received by an object. The unit of measure used to describe this is candela (cd).
7. Amount of substance (n) is the number of moles. The basic unit is the mole or mol.