# SI System of Units: What are they? Disadvantages & Advantages

**SI System of Units is** **the tool with which we can effectively measure all physical quantities. For example, if we want to measure length, it can be measured in meters, centimeters, feet, etc. If we need to measure mass, it can be measured in kilograms, grams, etc. are several units with which a certain amount can be measured.**

**If we now also take the other physical quantities, there are many units available for a certain amount. This creates confusion within ourselves. We may wonder which ones to choose and which not.**

**If there are many units available there may be a conversion factor to convert them to the other unit but it is very clunky and there is also a high risk of error if we do this and if we have to when we have that particular unit in the third unit measure that is available for the quantity, we may get the wrong result.**

**It is therefore imperative to choose standard sizes when measuring. In this case we only choose one unit for a certain amount. This unit is called the standard unit. Most of the measurements are carried out in this device. This makes the measurement easy, but it is also important that a certain size is expressed in a unit.**

**SI System of Units**

**Most of us know what SI units are, but we don’t know what SI means. It simply means international systems of units. The units used to measure physical quantities are collectively referred to as SI units. **

**It was developed and recommended in 1971 by the General Conference on Weights and Measures for international use in scientific, technical, industrial and commercial work.**

**Now the problem arises: which units should we choose? The selected units must have the following properties:**

**It must be a reasonable size.**

**It has to be precisely defined.**

**This has to be easily accessible.**

**It has to be time-independent.**

**It should not change with the change in physical size**

**SI units that are represented without the help of other quantities called basic quantities, such as length, temperature, etc.**

** Units that can be represented using basic units are called derived units.**

**The basic sizes and their standard units (SI) are:**

## SI Base Units

## Advantages of SI Units

**It is a coherent system of units.**

**It is a rational system of units.**

**SI is a metric system. **

**Conclusion of SI Units**

**While this has great advantages and we now use SI units for most measurements, it is not without its disadvantages either. **

**It has such disadvantages that it is mostly focused on one unit, so that the importance of other units is diluted. In addition, the SI unit cannot always precisely define a quantity.**

** For example, in the case of measuring the area covered by a house, in most cases we will use square feet as the unit of area, so in these situations we may need to convert to SI units, which is not desirable Fall can occur in other situations as well, but the advantages of SI systems are more dominant, that is why they are so popular and we use them quite often.**