# Physical Quantities and their Units

Physical Quantities
All the quantities which can be measured directly or indirectly in terms of which the laws of Physics are described are called physical quantities.

We are giving a detailed and clear sheet on all Physics Notes that are very useful to understand the Basic Physics Concepts.

## Physical Quantities and their Units, Symbols, Definition

Units
A standard amount of a physical quantity chosen to measure the physical quantity of the same kind is called a physical unit. It should be easily reproducible, internationally accepted.

Fundamental Quantities and Their Units
Those physical quantities which are independent to each other are called fundamental quantities and their units are called fundamental units.

### Supplementary Fundamental Quantities and Their Units

Radian and steradian are two supplementary fundamental units. It measures plane angle and solid angle respectively.

Derived Quantities and Their Units
Those physical quantities which are derived from fundamental quantities are called derived quantities and their units are called derived units e.g. Velocity, acceleration, force, work etc.

Units and Measurement Topics:
Measurement requires tools to provide scientists with a quantity. A quantity describes how much of something there is and how many there are.