120 likes | 207 Views
WU 8/31. Create the following data table in your notes. WU 9/1 **Take Out HW**. Read page #1 of the Syllabus What category of this class has the most effect on your grade? When you walk into the room each day, what is expected of you?
E N D
WU 8/31 • Create the following data table in your notes.
WU 9/1 **Take Out HW** • Read page #1 of the Syllabus • What category of this class has the most effect on your grade? • When you walk into the room each day, what is expected of you? • As simply as possible, state the tardy policy for this class. • What is the policy on late work? • What is the URL for the class website?
WU 9/2 • Adjust your data table from yesterday.
In your notes… • Write what you think the word significant means.
3-1 Significant Figures • Measurements have some uncertainty. • When taking a measurement, significant figures are : • all the digits that are known, • plus one digit of uncertainty, or a guess.
Rules for significant figures: 1. EX: 4.564 has ____ significant figures • Every nonzero digit in a reported measurement is assumed to be significant. • 5.62 has _____ significant figures. • 2. EX: 4.056 has ____ significant figures • Zeros between nonzero digits are significant. • EX: 5.0725 has ___ significant figures.
Rules 3 and 4 3. EX: 0.000435 has _____ sig. figs. • Leftmost zeros in front of nonzero numbers are not significant. • EX: 0.0021 • 4. EX: 5.0540 has _____ sig. figs. • Zeros at the end of a number to the right of a decimal place are significant. • EX: 9.210500
Rule 5 EX: 50400 has _____ significant figures. • Zeros at the end of a measurement, to the left of a decimal place are not significant. • If a decimal place is included after the zeros, count the zeros as significant. • EX: 649000. has _____ significant figures.
Rule 6 EX: There are 34 students in this class • Given values, or exact quantities have infinite significant figures
Practice • How many sig figs are in the following numbers? • 3.0345 • 6.230 • 0.0000678
How many significant figures are in the following measurements? • 5.6780 g • 0.00381 s • 679000.0 m • 6.0834 kg • 5 apples • 3.000 cm a. 5 b. 3 c. 3 d. 5 e. Infinite f. 4
Significant Figures & Math • In General: calculated measurements are only as good as their weakest link (fewest sig figs) • Addition & Subtraction • round answer according to fewest decimal places. (Don’t count digits to the left of the decimal place) • Multiplication & Division • Round answer according to fewest significant figures in measurements (Count ALL digits) • **These rules are on p. R60 as well