1. Unit 2: Physics
Sc 3200

3. Measurement and Calculations
Significant Figures - are numbers or digits that carry value (meaning) in a scientific problem or equation

4. Rules for Counting Sig Figs
There are five (5) rules we need to follow when counting sig figs:
All non-zero numbers are significant ( that is numbers 1-9)
Sandwiched zeros are significant
Leading zeros are NOT significant
Trailing zeros with a decimal are significant
Trailing zeros without a decimal are NOT significant

5. All non-zero numbers are significant (that is numbers 1-9)
Example:
123 has 3 sig figs
has 5 sig figs

6. 2. Sandwiched zeros are significant
Example:
1001 has 4 sig figs
901 has 3 sig figs

7. 3. Leading zeros are NOT significant
Example:
has 1 sig fig
0202 has 3 sig figs
.003 has 1 sig fig

8. 4. Trailing zeros with a decimal are significant
Example:
10.00 has 4 sig figs
has 6 sig figs

9. 5. Trailing zeros without a decimal are NOT significant
Example
has 3 sig figs
1900 has 2 sig figs

10. Practice Questions!