The Metric System

1. The Metric System

2. The Metric System • All scientific measurements are made using the Metric System. • It is also called the SI System (La Systeme International d’Unites) • The United States is the only major country that does not use this system.

3. Very Easy To Use Hint There are base units and prefixes Based on10(10 and 100 and 1,000) so you multiply or divide by 10 when converting It’s a decimalsystem… Can you think of a system we use every day that is adecimal system? ___________

4. Metric Base Units(last names) Length (how long it is)meter Volume (how much space it takes up)liter (for liquids) meter3 (for solids) Mass (how much matter is in it)gram Temp. (how much heat it has) °Celsius Time (how long it takes)second

5. How Do We Measure Them? (tools) Length Temperature Volume Time Mass

6. Metric Prefixes 1000 100 10 1/10 (0.1) 1/100 (0.01) 1/1000 (0.001) BASE UNIT 1 kilo hecto deka deci centi milli

7. Moving the Decimal for Length Larger Units, Smaller Number Smaller Units, Larger Number Base Unit

8. Let’s make it easier What’s a millimeter ? About the thickness of a paperclip What’s a centimeter? About the width of your pinkie finger What’s a meter? Height from the floor to the door knob

9. The length of the yellow line in centimeters (there will be a decimal) is _______ cm The length of the yellow line in millimeters (there will not be a decimal) is _______ mm

10. Mass • The mass is the amount of matter (or stuff) in an object and never changes unless you change the object. • We use a triple beam balance to find the mass of an object in grams.

11. Mass vs. Weight • The weight of something is the amount of gravity pulling down on an object and willchange if you go somewhere with more or less gravity. • Mass is NOTthe same as weight!

12. Moving the Decimal for Mass Larger Units, Smaller Number Smaller Units, Larger Number Base Unit

13. Use the triple beam balance to find the mass of a football in grams?

14. Volume • The volume is the amount of space an object takes up. • For liquids or oddly-shaped solids, we use a graduated cylinder or beaker to find the volume in liters (or mL).

15. Volume glug, glug, glug • The surface of the liquid might look slightly curved. • This curve is called the meniscus and we read the amount of mL from the lowest point of the meniscus.

16. Volume boom,boom,boom • For easy-to-measure solids (like a cereal box), we use a rule to find the volume in cubic meters (m3). • Volume (m3) = Length x Width x Height

17. Moving the Decimal for Volume Larger Units, Smaller Number Smaller Units, Larger Number Base Unit

18. Use the meniscus (lowest point of the water’s surface) to find the volume of the water (there will be a decimal). The volume is about _______ mL.

19. Measuring Mass and Volume • Take out a new piece of paper and do the following: • Put your name and hour in the top right hand corner • Write 1. Mass and then skip 5 lines • Write 2. Volume of a liquid and then skip 5 lines • Write 3. Volume of a solid and then skip 5 lines

20. Density • Density is the amount of matter (mass) per given space (volume) • Density = Mass (g) ÷ Volume (mL or cm3) • For example, water’s density is 1 g/mL which means that there is 1 gram of matter in every mL of water.

21. Density Think of it like a suitcase… the more clothes you try to fit in a suitcase, the more packed it gets. More packed = More dense

22. Density When you compare the density of two or more objects, the denser objects will sink below the less dense objects. For example, if an object has a density of 2 g/mL … what will it do in water? What if an object has a density of 0.2 g/mL?

23. Density • EXAMPLE OF SAME MASS (151 g): Spongebob Mac & Cheese Easter jelly beans • EXAMPLE OF SAME VOLUME (5,452 cm3): Red Swirly bowling ball Spider Web bowling ball

24. Density REMEMBER: Denser objects sink below less dense objects! • Number your paper 1 – 5 • Order the following objects from least dense (#1) to most dense (#5): • Water (blue), Syrup, Oil, Rubbing Alcohol (green), Oil, and Dish Soap