Significant Digits

1
Significant Digits
Precise
-Method scientists use to record measurements
calculations-Indicates precision in measurements
calculations-You cant report numbers better
than the method used to measure them-Includes
digits known precisely one estimated Rules1)if
Decimal, then zeros in front of the not
significant2)if No Decimal, then zeros at end of
the not significant ex/3000 (1) 0.005 (1)
400 (1) 400. (3)
3040 (3) 2.000 (4) 0.0045 (2)
6040 (3) Scientific Notation-Used when
reporting extremely large or small
numbers ex/240000 2.4 x 105 74000
7.4 x 104 0.00024 2.4 x 10-4
2.85 x 10-2 .0285
Uncertainty-from measurement lab
2
Addition Subtraction-Answer can only have the
same of digits after the decimal point as the
measurement with the least number of digits to
the right of the decimal point. ex/27.990
3.24 8.3
39.53 39.5 Multiplication
Division-Answer can only have the same of
significant digits as the number with the least
number of significant digits. ex/3.21
2.011 ? 3.7
23.884647 24
32.1 7.4? 2.11 41.61 41.6
2.31 1.8? 8.23 34.22034 34