Fundamental units of SI system | What is SI system?

Fundamental quantities and units of SI system

Looking at the different physical quantities, it appears that different units will be needed to measure it, but this will increase the number of units so much that it will be impossible to remember them. We know that many physical quantities are related like we Relate speed to distance or length and time. Speed ​​is equal to distance upon time, so speed can be expressed in units of distance and time. 

What is SI system?

Actually all the quantities in mechanics are expressed in units of length mass and time. It is known that the units of these three Physical quantities  are completely independent from each other and it cannot be changed or related to any other unit, hence these Physical quantities are called basic Physical quantities and their units are the base units, thus electromagnetic. 

In order to determine the quantities of the quantities coming in the Heat dynamics and optics, the electric current, heat and light intensity are considered to be the basic quantities. Their units are also called basic units. Assuming this quantity as the original amount, the basic unit has been set for it. The above basic amounts are electric standard, heat current and the unit system based on the quantity of the substance quantity is the international standard method.