Significant Figures- Rules

Significant Figures – digits of a number that carry meaning contributing to its accuracy. Reflection of instrument precision.

- You cannot be more accurate than your least precise measurement!

Uncertainty - point to which an estimation is taken while taking a measurement reading. Based on the calibration of the instrument

• measure to what you can see, and estimate one decimal place further!!!

Ex.1

3.23 cm

3.235 cm

Significant Figures – digits of a number that carry meaning contributing to its accuracy.

- You cannot be more accurate than your least precise measurement!

Rules: *Non-zero digits are significant.*

1. Enclosed zeros are significant. (aka sandwiched)

Ex: 1107 (4 sig figs) or 50.002 (5 sig figs)

2. Leading zeros are NOT significant.

Ex: 0.235 (3 sig figs) or 0.0000164 (3 sig figs)

3. Zeros at the end of a number are significant if they are to the right of the decimal point.

Ex: 0.2000 (4 sig figs) or 1.2500 (5 sig figs)

Ex: 3.2505

Ex: 0.006700

Ex: 400

Ex: 400.0

5 significant figures

4 significant figures

1 significant figure

4 significant figures