In this note, we are going to know about a topic called “What is System of Unit in Physics?“, and types of system of unit in physics. Welcome to Poly Notes Hub, a leading destination for engineering notes for diploma and degree engineering students.
Author Name: Arun Paul.
What is System of Unit in Physics?
A complete set of units, both fundamental and derived for all kinds of physical quantities is called system of units.
Types of System of Unit in Physics
There are four types of system –
- CGS system or Gaussian System: In this system the fundamental quantities are length, mass, and time and their respective units are taken as centimeters (cm), grams (g), and second (s).
- FPS System: In this system length, mass, and time are taken as fundamental quantities and their base units are foot (ft) pound (lb)and second (s) respectively.
- MKS System: It uses meter, kilogram, and second as the fundamental units of length, mass, and time respectively.
- SI units Or International System Of Units: The system of units, which is accepted internationally for measurement is the international system of units, abbreviated as SI, and is the modern form of metric system finally agreed upon at the eleventh International Conference of weights and measures, 1960.
Fundamental Quantities and Their Units
Below we have listed some basic or fundamental quantities and their SI Unit –
| Fundamental Quantities | SI Unit | Symbol |
|---|---|---|
| 1. Length | metre | m |
| 2. Mass | kilogram | kg |
| 3. Time | sec | s |
| 4. Electric Current | ampere | A |
| 5. Temperature | kelvin | K |
| 6. Luminous Intensity | candela | cd |
| 7. Amount of Substance | mole | mol |