Significant Figures Cheat Sheet - Mr. Brown's Science Town



Rules for Determining the Number of Significant Figures in a Measurement All non-zero digits are counted as significant figures.Examples: 673, 6.73 and 0.673 all contain 3 significant figures.Zeros between non-zero digits are counted as significant figures.Examples: 506 and 701 both contain 3 significant figures.Zeros in the beginning of a number whose only function are to be placeholders are not significant.Examples: 0.0000145 and 0.00905 both contain 3 significant figures.Zeros at the end of a number and to the right of a decimal point are always counted as significant.Examples: 0.120, 91.0 and 0.00000530 all contain 3 significant figures.Trailing zeros in a number are counted as significant only if the number contains a decimal point.1200 has two significant figures but 1200. has 4 significant figures.All numbers in a coefficient (when using scientific notation) are significant.8.924 X1012 contains 4 significant figures. An exact number is a number that arises when you count items or sometimes when you define a unit (use a constant). These are not measured quantities. They do not influence the number of significant figures an answer must be rounded to after a calculation. Calculations Using Significant FiguresWhen multiplying and dividing, limit and round to the least number of significant figures in any of the factors.Ex. 5.941 m X 6.2 m = 36.8342 m2What should the rounded value equal?When adding and subtracting, limit and round your answer to the least number of decimal places in any of the numbers that make up your answer.Ex. 9.61 g + 43 g + 789.065 g = 841.675 gWhat should the rounded value equal?Practice Problems:Determine the number of significant figures in the following:769.00_____________________0.00006740_____________________210._____________________9.8 X 104_____________________Round the following values to 3 significant figures.167.53sec_____________________8962222 km_____________________0.0000000000045789g_____________________33 K_____________________Solve the following problems using the correct number of significant figures.7.1 km ÷ 0.00410 sec = _____________________8.991 cm + 6.0 cm + 50 cm = _____________________0.0009371 m X 12005 m = _____________________ ................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download