Measurements 1.2 Scientific Notation Copyright © 2009 by Pearson Education, Inc.

2 Scientific Notation is used to write very large or very small numbers. for the width of a human hair of m is written 8 x m. of a large number such as s is written 4.5 x 10 6 s. Copyright © 2009 by Pearson Education, Inc.

3 Numbers in Scientific Notation A number written in scientific notation contains a coefficient. power of 10. Examples: coefficient power of ten coefficient power of ten 1.5 x x 10 -4

4 Writing Numbers in Scientific Notation To write a number in scientific notation, move the decimal point to give a number 1-9. show the spaces moved as a power of 10. Examples: = 5.2 x = 1.78 x spaces left 3 spaces right

5 Some Powers of 10

6 Comparing Numbers in Standard and Scientific Notation Here are some numbers written in standard format and in scientific notation. Number in Standard Format Scientific Notation Diameter of the Earth m 1.28 x 10 7 m Mass of a typical human 68 kg 6.8 x 10 1 kg Length of a pox virus cm 3 x cm

7 Study Tip: Scientific Notation In a number 10 or larger, the decimal point is moved to the left to give a positive power of 10 In a number less than 1, the decimal point is moved to the right to give a negative power of 10

8 Learning Check Select the correct scientific notation for each. A m 1) 8 x 10 6 m,2) 8 x m,3) 0.8 x m B g 1) 7.2 x 10 4 g, 2) 72 x 10 3 g,3) 7.2 x g

9 Solution Select the correct scientific notation for each. A m 2) 8 x m B g 1) 7.2 x 10 4 g

10 Learning Check Write each as a standard number. A. 2.0 x L 1) 200 L,2) L, 3) L B. 1.8 x 10 5 g 1) g, 2) g, 3) g

11 Solution Write each as a standard number. A. 2.0 x L 3) L B. 1.8 x 10 5 g 1) g