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 –
- All non zero digits are significant figure , and all zeros occurring between the two non zero digits are significant.
- 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.
- 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 .)