The measurement is the result of the comparison of standard and the unknown quantity. The result of the measured quantity is generally expressed in numeric forms. In other words, the measurement is the process through which the physical parameters like heat, displacement, force etc. is converted into the easily readable numeric value.
Methods of Measurement
The different methods of measurement are explained below in details.
Direct Method of Measurement – In this method of measurement, the unknown quantity is directly compared with the standard quantity. The result of the quantity is expressed in number. It is the most common method of measuring the physical quantities like length, temperature, pressure, etc.
Example: The physical balance directly measures the weight of the matter.
Indirect Method of Measurement – The direct measurement gives the inaccurate results in most of the cases. Hence, the direct method is rarely preferred for measurement. In indirect method of measurement, the physical parameters of the quantity are measured by the direct method, and then the numerical value of the quantity is determined by the mathematical relationship.
Example: The length, breadth and height of the substance is measured by the direct method and then by the help of the given relation the weight of the substance is known.
Weight = Length X Breadth X Height X Density
Method of Measurement without Contact – The sensor remains untouched with the object whose characters need to be measured.
Method of Combination measurement closed series – The result of the direct or indirect method of measurement are used for solving the equations.
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