Different methods of measurement- There are two methods of measurement-
1. Direct measurement method
2. Indirect measurement method
Direct measurement method-
Direct comparison with standard
In this method of measurement, we compare the quantity with primary standard or secondary standard.
Ex- If we have to measure the length of a bar, we measure it with the help of a tape (Secondary standard).
Even if we make the comparison directly with the secondary standard, it is not necessary for you to know the primary standard.
Primary standard- These are the original standard, made from certain standard values and formulas.
Secondary standard- These are made from primary standard.
Indirect measurement method-
Indirect comparison with standard
There are no. of quantities that cant is measured directly by using some instruments.
Ex- We can’t measure the strain generated on an elastic iron piece with the help of some secondary standards eg measure tape, weighing machine.
For that, we need to know the formula which gives a relationship between force and strain.
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