Question

Based on Significant Figures
14. What do you mean by significant digits ? Explain addition and subtraction quantities using idea of significant digits.
[Refer Art. 2.26]​

Answer 1

Answer:

★ Every experimental measurement has some amount of uncertainty associated with it. However one would always like the results to be precise and accurate.

★ Significant Figures are meaningful dgits which are known with certainty. The uncertainty is indicated by writing the certain digits and the last certain digit.

➡ For e.g., if we write a result as 11.2 mL, we say that 11 is certain and 2 is uncertain and the uncertainty would be +/- 1 in the last digit.

★ For addition and subtraction of significant figures, the result cannot have more digits to the right of the decimal place that either of the original numbers.

➡ For e.g.,

12.11 + 18.0 + 1.012 = 31 . 122

Here, 18.0 has only one digit after the decimal place and the result should be also upto one digit of decimal place that is 31.1

And this same rule goes for subtraction also.