Significant Figures Rules and Practice

Vocabulary flashcards reviewing fundamental rules and conventions for identifying and computing with significant figures from lecture notes.

Leading Zeros

Zeros at the beginning of a number that never count as significant figures (for example, in $0.00003$).

Trailing Zeros

Zeros at the end of a number that only count as significant figures if there is a decimal point present (for example, counted in $30.000\,\text{m}$, but not in $30\,\text{m}$).

Zeros Between Non-Zero Numbers

Zeros situated between two non-zero digits that always count as significant figures (for example, the zero in $0.0000305$).

Significant Figures in Scientific Notation

Only the digits shown in the coefficient or base portion count as significant figures, while the power of ten is excluded (for example, in $3.05 \times 10^{-4}\,\text{m}$).

Multiplication and Division Rule for Significant Figures

The measurement or number with the fewest significant figures determines how many significant figures the final answer can have.

Addition and Subtraction Rule for Significant Figures

Units must agree, and the result is rounded based on decimal place alignment rather than total significant figures (for example, $25.3 + 0.35 = 25.65$, which rounds to $25.7$).