Professor Tantama explains significant figures (or sig figs) in the short video below! Feel free to use it as an introduction (or reintroduction) to the topic. Then, keep coming back to this page as a reference throughout the semester as you work with significant figures.
Note: When uncertainty is known, disregard the rules below and use uncertainty to determine the number of significant figures that should be shown:
Round uncertainty to one significant figure.
Round your value to the same digit (i.e. 54.3 ± 0.2 are both rounded to the tenths place).
See attachments below for sig fig practice worksheet
See attachments below for uncertainty practice worksheet
See the Appendix section on Uncertainty Analysis for how you propagate uncertainties through your calculations to obtain the final AU on your final calculated answer.
Reference: Taylor, John R., An Introduction to Error Analysis