Download presentation

1
Ch. 2 Sec. 1 Measures in Science

2
**Metric System & SI Units**

French Scientists adopted metric system in 1795 Metric system uses powers of 10 10 millimeter = 1 centimeter 10 centimeter = 1 decimeter 10 decimeter = 1 meter There are 7 base units

3
**Base units Chart SI Base Units Base Quantity Base Unit Symbol Length**

Meter m Mass Kilogram kg Time Second s Temperature Kelvin K Amount of Substance Mole mol Electric Current Ampere A Luminous Intensity Candela cd

4
**Derived units Combination of the base units**

Speed or velocity = meters per second, m/s Energy = joule, kg m2/s2

5
**SI Unit Prefixes Prefix Symbol Multiplier Sci. Notation Pico p**

1/1,000,000,000,000 10-12 Nano n 1/1,000,000,000 10-9 Micro 1/1,000,000 10-6 Milli m 1/1,000 10-3 Centi c 1/100 10-2 Deci d 1/10 10-1 Kilo k 1000 103 Mega M 1,000,000 106 Giga G 1,000,000,000 109 Tera T 1,000,000,000,000 1012

6
Scientific Notation Able to make using really large or small numbers easier Expressing decimal numbers in powers of 10 N x 10n Move decimal point until only one non-zero digit remains Count the number of spaces and use that as exponent Earth to Mars = m 2.278 x 1011m Mass of electron = kg 9.11 x 10-31kg

7
**Express in Sci. Notation**

5800 0.004

8
**Express in Sci. Notation**

9
**Converting Units What is the equivalent in km of 670 m?**

1 km = 1000 m (1000 m)/ (1 km) = 1 Using a Conversion Factor you can determine the relationship between two units Multiplier equal to one 670 m = (670 m) (1 km / 1000 m) (670 m x 1 km) / 1000 m = km Label units will cancel out

10
**Converting Units Practice**

1.1 cm meters 76.2 pm millimeters 2.1 km meters 2.278 x 1011 m kilometers 147 g kilograms 11 Mg kilograms 7.23 µg kilograms 478 mg kilograms

11
**Converting Units Practice**

1.1 cm 1.1 x 10-2 m 76.2 pm 7.62 x 10-8 mm 2.1 km 2.1 x 103 m 2.278 x 1011 m x 108 km 147 g 1.47 x 10-1 kg 11 Mg 1.1 x 104 kg 7.23 µg 7.23 x 10-9 kg 478 mg 4.78 x 10-4 kg

12
**Adding and Subtracting in Sci. Notation**

When adding or subtracting, make sure the powers of 10 are the same (10N) 4 x x 108 (4 + 3) x 108 7 x 108 (4.1 x 10-6) – (3.0 x 10-7) (4.1 x 10-6) – (0.30 x 10-6) (4.1 – 0.30) x 10-6 3.8 x 10-6

13
**Multiplying & Dividing in Sci. Notation**

Multiply or divide the values and the units Add (if multiplying) or subtract (if dividing) the exponents (4 x 103 kg)(5 x 1011 m) (4 x 5) x kg•m 20 x 1014 kg m 2 x 1015 kg m (8 x 106 m3) / (2 x 10-3 m2) (8/2) x 106 – (-3) m(3-2) 4 x 109 m If units have powers, add or subtract accordingly

Similar presentations

© 2020 SlidePlayer.com Inc.

All rights reserved.

To make this website work, we log user data and share it with processors. To use this website, you must agree to our Privacy Policy, including cookie policy.

Ads by Google