2. The International System of Units Also known as SI units It is the modern day metric system It is a form of measurement used all around the world

3. When was SI created? The system of measurement was created in 1960 after the General Conference on Weights and Measures asked the International Committee for Weights and Measures to conduct a study on international measurements. In 1954, they created six base units: Meter, kilogram, second, ampere, Kelvin, and candela

4. When was SI created? (cont.) In 1960, they created the name International System of Units, abbreviated SI, from the French name: Le Systeme international d’unites. They added ONE more SI unit (mole) in 1971

5. SI units, Symbols and Quantity NameSymbolQuantity MetermLength KilogramkgMass SecondsTime AmpereAElectric Current KelvinKThermodynamic temperature MolemolAmount of substance CandelacdLuminous intensity

6. The Metric System A system of measurement based on the number “10” Records show it was used in the mid 1500’s Used ALL over the world as the main system of measurement, EXCEPT in these countries: Liberia Burma The United States

7. Prefixes PrefixSymbolMeaning Kilo-k1,000 Hecto-h100 Deka-da10 UnitJust the unit1 Deci-d0.1 (one tenth) Centi-c0.01 (one hundredth) Milli-m0.001 (one thousandth)

8. Length Definition- the distance from one point to another Basic SI Unit- meter (m) Tools to measure length- metric ruler (centimeters) Meter stick (100 centimeters)

9. Mass Definition- the measure of the amount of matter in an object. Basic SI Unit- kilogram (k) Tools to measure mass: Scale Triple Balance Beam

10. Difference between Mass and Weight Mass- the amount of matter in an object Weight- a measure of the force of gravity acting on an object. It is measured using a scale. You mass is the same, no matter where you go. Your weight changes due to gravity. Ex: You weigh 100 lbs on Earth. If you went to the moon, you would weigh 16.6 lbs.

11. Volume Definition- the amount of space an object takes up. Basic SI Unit- Liter (L) Tools to Measure Volume: Volume of a Liquid- graduated cylinder (L) Volume of Rectangular Solids- Length x Width x Height (cm3) Volume of Irregular Solids- Water displacement

12. Density Definition- a measure of how much mass is contained in a given volume. Units- g/cm 3 or g/mL Calculate- Density= Mass/ Volume

13. Time Definition- Basic SI Units- second (s) Tools for measure time- Clocks Watches

14. Temperature Definition- How warm or cold something is Basic Units of SI- Kelvin (K) Scientists use Celsius (C) Tools to Measure Temperature- Thermometer

15. Conversion between Units How do you convert Meters to Centimeters? 1. Write down the number you want to convert and its proper unit. Ex: 100 meters = ? cm 2. If the number is a whole number, add the decimal point at the end of the number. Ex: 100. meters 2. Using the conversion chart, move the decimal point towards the proper unit.

16. Conversion Chart Kilo 1000 Hecto 100 Deka 10 Unit Deci 0.1 Centi 0.01 Milli 0.001