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Different system of units

In this article we are going to study about Different systems of units and describe them individually. We are going to study the advantages of different types of systems and we will discuss some important topics related to it.

If there are several units available, there may be a conversion factor to convert it into the other unit, but this is awkward and there is a significant risk of error, so if we need to measure that particular unit in the third unit available for the quantity, we may end up with an incorrect result.

As a result, choosing standard quantities in measurement is absolutely necessary. In this scenario, we choose a single unit for a specific quantity, which is referred to as a standard unit. The majority of the calculations are carried out in that unit. As a result, not only does the measurement become simpler, but it also emphasises the value of a single unit for a certain quantity.

SI System of units

Units are defined as the tools that allow us to accurately measure any physical quantity. For example, if we want to measure length, we may use metres, centimetres, feet, and so on; similarly, if we want to measure mass, we can use kilograms, grams, and so on. We can conclude that there are various units that can be used to measure a specific quantity.

We all know what SI units are, but we have no idea what SI stands for. It simply refers to international metric systems. SI units are a collection of units used to measure physical quantities. In 1971, the General Conference on Weights and Measures developed and recommended it for international use in scientific, technical, industrial, and commercial operations.

The units selected must possess the following characteristics:

  • It should be of a sufficient size.
  • It must be precisely specified.
  • It must be easily accessible.
  • It has to be independent of time.
  • It should remain constant regardless of changes in physical quantity.

The SI units are those that are represented without the use of other fundamental quantities such as length, temperature, and so on. The units that can be represented using the fundamental units are referred to as derived units.

Advantages of SI System of units 

  • It is a coherent system of units.
  • It is a rational system of units.
  • The International System of Units (SI) is a metric system. 

Conclusion of SI System of units

Though it has many advantages, and we now use SI units for the majority of measurements, it also have drawbacks. It has drawbacks, such as mainly focusing on one unit, diluting the relevance of other units. Furthermore, the SI unit does not always precisely represent a quantity.

MKS System of units

The MKS system of units is a physical measurement system based on the metre, kilogram, and second (MKS). The International System of Units (SI) is based on it, though SI has since been redefined by new fundamental constants.

(In the metric-kilogram-second system) The metre, kilogram, gram, and second are all units of length, mass, and time in the metric system. The “newton” and “joule” are the units of force and energy, respectively. SI, newton, and joule are all terms that can be used to describe a unit of measurement. In comparison, consider the CGS system.

CGS System of units

The centimetre–gram–second (abbreviated CGS or cgs) system of units is a variation of the metric system that uses the centimetre as the unit of length, the gram as the unit of mass, and the second as the unit of time. All CGS mechanical units are explicitly derived from these three foundation units, however the CGS system was extended in a variety of ways to include electromagnetism.

The CGS system was largely replaced by the MKS system, which was extended and replaced by the International System of Units, which was based on the metre, kilogramme, and second . SI is the only system of units used in many sectors of research and engineering, while CGS is still widely used in several subfields.

The MKS system, which is based on metre, kilogram, and second, has essentially replaced the CGS system. The International System of Units was then extended and superseded by MKS (SI). The ampere, mole, candela, and kelvin are added to the three MKS base units. Although SI is the only system of units used in many domains of research and engineering, there are still specialized areas where the CGS system is used.

FPS System of Units

The foot, pound, and second, which represent the base dimensions of length, mass, and time, respectively, are the base units of the FPS system. The foot per second and poundal are the complex units of speed and force, respectively, with 1 poundal equalling 1 foot pound per second squared.

Conclusion 

In this article we have studied about Different type of system and look at them individually. A system of units is a collection of linked units used in calculations. Base units, which represent base dimensions, and derived units, which represent products of powers of base dimensions, make up the system. Some units are found in multiple systems of measurement.

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Define SI System of units?

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state some application of SI System of unit?

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Define FPS System of unit?

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Explain CGS System of Units?

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