1. SIGNIFICANT FIGURES

2. Significant Figures
When a scientist makes a measurement, he or she is allowed to estimate one digit.
Consequently, the last digit of any measurement is always considered to be uncertain since it has been estimated.

3. Significant Figures
Significant digits (figures) include all
measured (certain) digits plus one estimated (uncertain) digit.

4. Significant Figures
The precision of measurement is an important part of experimentation. Precision refers to the degree of exactness with which a measurement is made and stated. This precision is indicated by the number of significant digits in the measurement.

5. Significant Figures accepted (actual) - experimental
Accuracy is not the same thing as precision. Accuracy refers to how close to the accepted value a measurement is. We often show the accuracy of a measurement or calculation with % error.
accepted (actual) - experimental
% error = x 100
accepted (actual)

6. Significant Figures
How do you determine the number of significant digits in a measurement???
All nonzero digits are significant.

7. Significant Figures
How do you determine the number of significant digits in a measurement???
2. A zero is significant if
It is the last digit to the right of a decimal.
It has a bar over it.
It is “sandwiched” between significant digits.

8. Significant Figures
If a zero doesn’t fit into one of these 3 categories, it is merely a place-holder and hasn’t been measured or estimated so it isn’t significant.