BASE UNITS AND DERIVED UNITS

 BASE UNITS 

 

• The units that  describes  base quantities are called base units.
• Each base quantity has its SI units.

DERIVED UNITS

• The units used to measure derived quantities are called derived units.
•  Derived units are defined in terms of base units and are obtained by multiplying or dividing one or more base units with each other. 
• The unit of area (metre2) and the unit of volume (metre3) are based on the unit of length, which is metre. 
• Thus, The unit of length is the base unit while the unit of area and volume are derived units. 
• Speed is defined as distance covered in unit time; therefore its unit is metre per second. 
• In the same way the unit of density,force, pressure, power etc. can be derived using one or more base units.