Measurement

The way of expressing the quantity of an object in numbers with units is known as measurement. Measurement involves determining the weight, height, volume, etc, of an object. Measurements are represented by certain units like meters, kilos, pounds, gallons, celsius, minutes, and so on.

When learning measurement, it is important to learn about how it all began. In ancient times, lengths were measured based on the human body. For e.g., they used the width of their thumb and length of their foot to measure things.     

Around 3000 BC, the Egyptian cubit was widely accepted as the standardized measuring unit. Based on the existing measuring idea, a standard royal cubit was used. The cubit was a black granite rod whose length was the same as the length of a royally-assigned arm.  

Harappan civilisation thrived in South Asia between 2500 and 1700 BC. Recent excavations at present-day Pakistan have proved that the Harappans had a uniform system of measures. Europeans, on the other hand, had adopted the Roman measuring system, which was originally based on those of Greece. 

When trade, industries, and travel expanded worldwide, a need for standardized measurement came. The need was intensified during the French Revolution, leading to the formation of the International System of Units (SI unit). The developed version of the SI unit is the metric system. Today, most countries follow the metric system while some countries like the US use the imperial system, also known as the US Standard system.
 

Have you heard words like meters, liters, grams, feet, inches, pounds, etc? These are the units of measurement. These are used to refer physical quantities such as length, weight, volume, etc. Now let’s understand the differences between standard units and non-standard units. 
 

We use different units and devices based on the physical qualities of an object. Weight, volume, length, time, temperature, area, and angle There are different physical qualities like.
 

The distance between two points is what we call length. Kilometer, meter, feet, inches, and so on are the units of length. 
 

Weight is the heaviness of an object as compared to the other. The units are grams, kilograms, pounds, tons, etc. 
 

Time is measured in seconds, minutes, hours, weeks, months, and years. Time is about the period of an event, which can be past, present, or future. 

Volume is the amount of substance a three-dimensional object can hold. The units used are liter, milliliter, quart, and gallon.

The amount of hotness or coldness of any object is the temperature. We usually measure temperature, commonly in either Celsius or Fahrenheit.
 

The space occupied by an object in a two-dimensional space is the area. Square units are the unit of measurement of area. Like square centimeters (cm²), square meters (m²), and square kilometers (km²).

The angle formed between two rays is the angle measurement. The units are degrees and radians.

Measurement instruments are the tools used to measure physical qualities of any object. They make our lives easy as they help us know accurate measurements of anything that needs to be measured. For e.g., a scale marked with graduations can be used to draw multiple parallel lines with equal spacing between each lines. For different objects based on their properties, different tools are used. So let’s see some commonly used measurement instruments.
 

Measurement tape is the instrument used to measure the length. Millimeters, centimeters, meters, inches, etc. are the units.
 

The instrument used to measure time is a clock. The units are seconds, minutes, hours, days, months, etc.
 

It is the instrument used to measure the weight of any object. Weight machines can be manual or digital.
 

Now we have learned about different types of measurements and units of measurement. All the measurement units are interconnected. 

Measurement conversion is the process of converting a unit from one to another. 
For example, 1 kg can be converted to 1000 g. Here we are going to learn more about measurement conversions in the metric system.

The metric system is based on the power of 10. That means, to convert from one unit to another, we will multiply or divide the value by 10.

Earlier, measurements were not accurate, as they used the human body, stones, and seeds to measure and there were no standardized units. This usually led to measurement errors. To avoid such errors, we use a standard form of measurement, which is known as the metric system and the US standard system (Imperial system). 
 

For each physical quality, we have different units of measurement. For an easier understanding of units of measurement in the two systems, you can refer to the measurement chart.

For metric system

For the US Standard system

The fundamental concept of physics, math, engineering, etc. is measurement. So when measuring any object, we need to follow certain rules. Some basic rules and properties of measurement are

Consistency: The value of measurement of an object should be the same, even if you measure it multiple times. 

Accuracy and Precision: The closeness of a measured value to the true value is accuracy. Whereas, the consistency of obtaining the same result when measuring the same object multiple times is precision.

Estimation: Estimation is making an approximate value for an object when there is a limitation. 

Standardization: Standardization refers to the use of a universally recognized unit for measuring.  
 

Whenever we measure, the measurement should be accurate and precise.  As we have learned all about measurements now, let's see some tips and tricks to master measurement. 

Understanding basic units 

Students should try to learn and memorize the basic standardized units of measurement. 

Using measuring tools effectively

For each physical quality, we have different measuring tools. When measuring try to use the correct measurement tool, and do the basic check before measuring.

Converting between units

As we know, metric system is based on the power of 10. So, when converting from one unit to another, we either divide or multiply it by 10. 

 For example, 1 km = 1000 m, so to convert from km to m we multiply it by 1000. That is 5 km = 5000 m. 

Measurement is all around us, we use it in the field of construction, cooking, sports and so on. Let’s explore how we use measurement in the real world.

Construction: In the field of construction we need accurate measurements of the length, width, and height of the building

Sports: In sports, we use measurement field measurement, the performance of the athlete, and progress 

Cooking: While cooking, we need to measure the ingredients