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Conversion of Units of Measurement

Measurement of any specific thing is a number that shows in what quantity it is present and measurement units are units that are used to define that amount of the physical quantity.

The world of science and mathematics is all about calculations. These calculations are all related to the measuring quantities and their units. From the time you wake up in the morning till you go back to sleep, you come across hundreds of basic physical quantities and they are all measured using a certain unit of measurement.

What is a unit?

Unit means single. It can be further defined as one single person or one single thing or even one single quantity. It can be called any quantity which is fixed in its original form and the standard to define the value of the physical quantity.

For example, a centimetre is a unit to measure the length of anything.

IMPORTANCE OF UNITS OF MEASUREMENTS

When we ask the question, why do we really need units of measurements, there is a very simple answer to this i.e., you need a communication channel way to convey the value of any specific physical quantity.

For example, if you are having a fever, you need to measure to what temperature your body is really heated to know the standard value to make any sense? Otherwise, you cannot describe the situation without a valid unit of measurement of that quantity.

Measurement units are important in our everyday life. Any measurement of any physical quantity around us is useless without its unit. If there is no unit to the physical quantities, they can never be defined as a value. It builds a relationship between the different values of measurements of any quantity.

Just think, how will you define a length or mass of any physical quantity without a unit to measure it? It will be so difficult to differentiate between any two quantities and everything will be vague.

7 BASIC UNITS OF MEASUREMENTS

There are 7 basic units of measurement of the 7 physical quantities i.e.,

  1.     Length is a physical quantity that is measured in metres. It is denoted by (m).
  2.     Time is a physical quantity that is measured in seconds. It is denoted by (s).
  3.     Electric current is a physical quantity that is measured in amperes. It is denoted by (A).
  4.     Amount of substance is a physical quantity that is measured in moles. It is denoted by (mole).
  5.     Mass is a physical quantity that is measured in kilograms. It is denoted by (kg).
  6.     Temperature is a physical quantity that is measured in kelvin. It is denoted by (K).
  7.     Luminous intensity is a physical quantity that is measured in candela. It is denoted by (cd).

SI UNITS AND THEIR HISTORY

There is the history behind every SI Unit of the physical quantity that we know. The metre which is now used to measure length was earlier defined as 1/10000000 of the distance of the north pole to the equator of our planet Earth. It was measured through Paris on the circumference. The kilogram which is now used to measure mass was earlier used to define the mass of a litre quantity. The seconds which measure time were earlier based on a one-day standard measurement of 24 hours. There have been many stories about the evolution of these standards of measurement. Some examples are, the SI Unit of force is Newton, SI Unit of density is kg/m3 etc.

CONVERSION

Before we measure anything, we need to know in what unit we are measuring the quantity. There are many ways to convert measurements. Some of the major ones are listed below.

For length, to convert km to m we multiply it by 1000, m to cm, we multiply it by 100, and for cm to mm, we multiply it by 10.

For mass or weight, to convert a tonne into kg, we multiply 1000, for Kg to g, we multiply 1000, and for gram to mg, again we multiply 1000.

For any capacity, l to cl, we multiply 100, cl to ml, we multiply 10, and for l to ml, we multiply 1000.

Some conversions need a formula. For example, Conversion of Celsius to Fahrenheit = (temperature in Celsius x 9/5) + 32. Similarly, Conversion of Celsius to Kelvin = temperature in Celsius + 273.15

CONCLUSION

Units and measurements are part of our daily life and we need them every second. Even in this sentence, the second is a unit of measuring time. And time is the physical quantity which is measured or denoted by seconds. Units and measurements provide you with a standard reference point for calculating values of the quantities that are present around you. It can be the length, mass, time, temperature, distance, speed, density, etc. There are hundreds of physical quantities and each has a point of measurement defined by a unit that makes them unique. The units are standardised by a SI Unit (International System of Units). This starts with 7 base units known as length (m), mass (kg), temperature (K), time (s), distance (km), amount of substance (mole), luminous intensity (cd), and electric current (A).

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Frequently Asked Questions

Get answers to the most common queries related to the Railway Examination Preparation.

What is a unit and unit of measurement?

Ans. It can be called any quantity which is fixed in its original form and the standard to define the value of the p...Read full

Give any two importance of units and measurement.

Ans. Units and measurements are important in our everyday life. Any two importance are: ...Read full

Convert 73 metres of length into centimetres and kilometres.

Ans. Original value = 73 m m to cm = (original value x 100) ...Read full

Convert 100 Celsius to Fahrenheit and Kelvin.

Ans. Conversion of Celsius to Fahrenheit = (temperature in Celsius x 9/5) + 32 ...Read full