What Do You Mean By Significant Figures Physics Q&A

Define significant figures:

Those digits in a number that are meaningful in terms of precision and accuracy are known as significant figures.

The larger the number of significant figures obtained in a measurement, the greater is the accuracy of the measurement and vice-versa.

Rules for Significant Figures

  • All non-zero digits are significant.
    198745 contains six significant digits.
  • All zeros that occur between any two non-zero digits are significant. For example,
    108.0097 contains seven significant digits.
  • All zeros that are on the right of a decimal point and also to the left of a non-zero digit are never significant. For example,
    0.00798 contained three significant digits.
  • All zeros that are on the right of a decimal point are significant, only if, a non-zero digit does not follow them. For example,
    20.00 contains four significant digits.
  • All the zeros that are on the right of the last non-zero digit, after the decimal point, are significant. For example,
    0.0079800 contains five significant digits.
  • All the zeros that are on the right of the last non-zero digit are significant if they come from a measurement. For example,
    1090 contains four significant digits.