Significant figure

Significant figure

In this topic we will discuss what is a significant figure ?  how can we find the significant figure in the given values and what are the rules for counting significant figure ?

Significant figure – It is the measured value of a physical quantity tell the number of digit in which we are confident .Larger the value of significant figure greater will be the accuracy and vice versa ).

Number of significant figure in a physical quantity depends upon the least count of the instrument used for its measurement.

Rules for counting significant figure –

  1. All non zero digits are significant figure , and all zeros occurring between the two non zero digits  are significant.
  2. In a number less than 1 , all zeros to the right of decimal point and to the left of a nonzero digit are not significant . But all the zeros on the right of the last non zero digit in the decimal part are significant.
  3. All zeros on the right of non zero digits are not significant . but all zeros on the right of the last non zero becomes significant when they come from a measurement.


(Note- change in the unit of measurement of a quantity does not change the number of significant figures .)


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