System Of Units

System Of Units

A set of fundamental units and derived units together is called a system of units.

In physics, there are two types of units such as fundamental and derived. In mechanics, most of the physical quantities depend upon three fundamental Physical quantities such as length, mass and time. Therefore the scientist Gauss in 1832, suggested selecting three fundamental physical quantities for expressing unit of derived physical quantities.

There are different types of physical quantities. For the measurement of each physical quantity, we require an Independent unit. Hence for convenience system of units was developed.

Following are the commonly used systems of units.

1) CGS system: [Centimeter Gram Second]

It is a French system in which C stands for centimeter G stands for gram and S stands for a second. In this system, basic units of length, mass and time are centimeter, gram and second respectively. This is a metric system.

2) FPS system: [Foot Pound Second]

It is a British system in which F stands for foot, P stands for pound and S stands for Second. In this system, basic unit of length, mass and time are the foot, pound and second respectively. This is not a metric system

3) MKS system [Metre Kilogram Second]

In this system, M stands for meter, K stands for kilogram and S stands for a second. In this system, basic units of length, mass and time are meter kilogram, second respectively. This is also a metric system.

4) SI system

The French name for this system is 'system of international d unities. It is abbreviated as SI. Conference of weights and measures decided a new system of units which is known as the SI system.

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