Transcript Significant Figures

Significant Figures
Your Goals for Today



Know how many significant figures are in
a number
Know how to multiply and divide using
significant figures.
Be able to give reasons why we use
significant figures
What are Significant Figures?




They are the numbers we care about in
experiments and calculations
Largely, used by scientists
Keep values accurate
Helps us put values into scientific notation
Significant Figures

1.
2.
3.
4.
The Rules:
Nonzero Numbers are always significant
Final Zeros (zeros at the end) after the
decimal place are significant
Zeros between numbers are significant
Zeros used only as placeholders are not
significant
Significant Figures
1.
Non Zero Numbers are always significant
3.2001
significant!!!
Significant Figures
2. Final Zeros following the decimal are significant
6.200
Significant
Significant Figures
3. Zeros between significant figures are
significant
6.204
Significant
Significant Figures
4. Zeros used only as place holders are not
significant
140.00
Significant
140
No decimal
point
Not significant
How many significant figures?
304
0.000004
8.5 kg
0.0070 m
6.2 x 105
30.00
0.00302
Significant Figures

Multiplying and Dividing with Significant
Figures
1. Count the number of
significant figures, find
the one with the least
2. Your answer will have that
number of significant figures
6.05
3 sig figs
11.72
4 sig figs
x 0.10
2 sig figs
7.1  2 sig figs
Significant Figures
You practice:
16.003
0.000075
x 220
0.26
5.1 x 103
3000.00
x 3000
5 x 1010
Your Goals When You Practice



Know how many significant figures are in
a number
Know how to multiply and divide using
significant figures.
Be able to give reasons why we use
significant figures