The SI system and units of measurement

Transcription

1 The SI system and units of measurement Scientists all over the world use a single measurement system called Le Systeme International d Units, Abbreviated SI. It was adopted in 1960.

2 Advantages of the Metric System Creates an international system of measurement that uses the same standards world wide Ease of recording and calculating All units are based on units of 10 Very precise measurements can be recorded with decimals NOT fractions.

3 Base Units Unit of Length- Meter Based on the distance from the N. Pole to the equator Unit of Volume- Liter The space an object takes up (solid, liquid or gas) Unit of Mass- Gram The amount of matter in an object Bill Nye

4 Metric prefixes This prefix A changes prefix that the The base of any makes base a into unit a 10x unit unit determined larger 1000x 100x than the by This what prefix larger you are changes base measuring This prefix the This prefix base changes into a the unit changes the 1/1000 base into as a large unit base into a unit 1/100 as the as base large 1/10 as large as as the base the base

5 K h DA - Base D C M Meter Liter Gram

6 King Hector Come up How with Died are a we sentence going By to order to remember Drinking the prefixes! these? Chocolate Milk

7 1 Ladder Method KILO KK000 Units 2 HECTO H Units DEKA DA Units 3 Meters Liters Grams DECI D1 Unit CENTI C Unit MILLI 0M1 Unit How do you use the ladder method? 1 st Determine your starting point. 2 nd Count the jumps to your ending point. 4 km = m Starting Point Ending Point How many jumps does it take? 3 rd Move the decimal the same number of jumps in the same direction = 4000 m

8 Conversion Practice Try these conversions using the ladder method mg = g 1 L = ml 160 cm = mm 14 km = m 109 g = kg 250 m = km Compare using <, >, or =. 56 cm 6 m 7 g 698 mg

9 Conversion Practice Try these conversions using the ladder method mg = g 1 L = ml 160 cm = mm 14 km = m 109 g = kg 250 m = km Compare using <, >, or =. 56 cm 6 m 7 g 698 mg

10 Metric Conversion Challenge Write the correct abbreviation for each metric unit. 1) Kilogram 4) Milliliter 7) Kilometer 2) Meter 5) Millimeter 8) Centimeter 3) Gram 6) Liter 9) Milligram Try these conversions, using the ladder method. 10) 2000 mg = g 15) 5 L = ml 20) 16 cm = mm 11) 104 km = m 16) 198 g = kg 21) 2500 m = km 12) 480 cm = m 17) 75 ml = L 22) 65 g = mg 13) 5.6 kg = g 18) 50 cm = m 23) 6.3 cm = mm 14) 8 mm = cm 19) 5.6 m = cm 24) 120 mg = g

11 Length The SI unit for length is meter. (m) A distance of 1m is about the width of an average doorway Longer distances are expressed in kilometers (km). 1 kilometer is = to 1000m. Shorter distances are expressed in centimeter (cm). 1 centimeter is = to 1/100m. Length can be measured using a meter stick or rulers.

12 Length 1. Always start at 0 2. Know what units you are using! m cm - mm

13 Volume =amount of space an object takes up. 3 ways to find volume Using a graduated cylinder Using the displacement method Calculating L X W X H

14 The marks on the cylinder are called graduations. That is why the instrument is called the graduated cylinder. Each mark on this cylinder is worth one milliliter The graduations on a cylinder are not always worth the same. Before using the cylinder, you need to figure out what each graduation is worth. When a liquid is put into a cylinder, the surface curves. This curve is called a meniscus. When reading the volume of a liquid, always read at the bottom of this curve while placing the container on a flat surface and bending down to look at the meniscus at eye level. Cohesion and Adhesion!! Water is sticky. To go to the next page, click on the right arrow key.

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16 The first thing you must do when using an instrument is to determine it s scale or to find out how much each line is worth. Write down the value of each line beside the diagram below Check you answers on the next page. To go to the next page, click on the right arrow key.

17 Answers to determining the scale of a graduated cyclinder. a. 1 ml b. 0.5 ml c. 5 ml d. 2 ml e. 10 ml To go to the next page, click on the right arrow key.

18 Images created at Measuring Liquid Volume What is the volume of water in each cylinder? Pay attention to the GRADUATIONS for each cylinder.

19 n/syllabus/unit14/new/testingmain1.htm Measuring Solid Volume 9 cm We can measure the volume of regular object using the formula length x width x height. 10 cm 8 cm X X = We can measure the volume of irregular object using water displacement. Amount of H 2 O without object = About of H 2 O with object = Difference = Volume = Click here for an online activity about volume. Choose Lessons Volume & Displacement

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