1. MEASUREMENT FOUNDATIONS OF SCIENCE

2. ESSENTIAL QUESTIONS WHAT IS A SCIENTIFIC MEASUREMENT? WHAT IS THE DIFFERENCE BETWEEN ACCURACY AND PRECISION? WHAT IS A SYSTEMATIC METHOD OF CONVERTING FROM ONE MEASUREMENT UNIT TO ANOTHER?

3. MEASUREMENT A DETERMINATION OF THE AMOUNT OF SOMETHING CONTAINS A NUMBER VALUE AND A UNIT THE NUMBER IS USELESS WITHOUT A UNIT ATTACHED

4. TWO COMMON MEASUREMENT SYSTEMS ENGLISH SYSTEM USED BY PEOPLE IN THE UNITED STATES – INVOLVES UNITS SUCH AS MILES, FEET, CUPS, TEASPOONS, POUNDS, PINTS, QUARTS, GALLONS AND INCHES – lots of different relationships INTERNATIONAL SYSTEM CALLED THE SYSTEM INTERNATIONAL (SI UNITS) AS COINED BY THE FRENCH AND ADOPTED BY THE UNITED STATES IN 1960 – INVOLVES UNITS WHICH ARE ALL BASE 10 OR IN THE DECIMAL SYSTEM

5. COMPARE THE TWO SYSTEMS ENGLISH SYSTEM – YARD STICK 1 YARD = 36 INCHES = 3 FEET SMALLEST DIVISION IS 1/32 ND OF AN INCH IN MOST CASES – A FRACTION OF AN INCH – TOUGH TO ESTIMATE THE MEASUREMENT SOMETIMES – based on fractions – ¼, 1/8, 1/16, etc. INTERNATIONAL SYSTEM – METER STICK 1 METER = 100 CENTIMETERS = 1000 MILLIMETERS SMALLEST DIVISION IS A 1/10 TH OF A CENTIMETER OR ONE MILLIMETER – NOT A FRACTION, BUT 0.1 – EASIER TO ESTIMATE THE MEASUREMENT – based on decimals!!

6. COMMON SI UNITS

8. ACCURACY OF A MEASUREMENT HOW CORRECT THE MEASUREMENT IS IS IT CLOSE TO THE TARGET VALUE YOU ARE AIMING FOR? DETERMINED BY CALCULATING A PERCENT ERROR FOR THE MEASUREMENT

9. CALCULATE THE PERCENT ERROR If the density of an object is found to be 7.62 g/ml in the laboratory, what is the percent error if the reference density is 7.48 g/ml?

10. PRECISION OF A MEASUREMENT HOW CLOSE THE REPEATED MEASUREMENTS ARE TO EACH OTHER HOW CONSISTENT THE MEASUREMENTS ARE FOR A MEASUREMENT, PRECISION IS REFLECTED IN HOW MANY SIGNIFICANT DIGITS ARE IN THE VALUE

11. PRECISION DEPENDS ON MEASURING INSTRUMENT WHICH INSTRUMENT HAS BETTER PRECISION IN MEASURING THE VOLUME OF WATER?

12. MAKE THIS MEASUREMENT In making a measurement, you are only allowed to estimate one digit. All other digits are known for certain!!! The digits known for certain and the one estimated digit are known as SIGNIFICANT DIGITS!!!!

13. ACTIVITY You will be working with a partner to complete a packet in which you thoughtfully make several scientific measurements, reporting all significant digits.

14. ACCURACY VS PRECISION

15. TIME TWO WAYS TO THINK ABOUT TIME WHAT TIME IS IT? HOW MUCH TIME? (TIME INTERVAL) TIME COMES IN MIXED UNITS YOU MAY NEED TO CONVERT HOURS AND MINUTES INTO SECONDS HOW MANY SECONDS DOES THE TIME INTERVAL REPRESENT?

16. DISTANCE THE AMOUNT OF SPACE BETWEEN TWO POINTS MEASURED IN UNITS OF LENGTH THE METER IS THE BASIC SI UNIT PREFIXES ARE ADDED TO REPRESENT EITHER MULTIPLES OF THE METER OR PARTS OF THE METER 1 MEGAMETER = 1,000,000 METERS 1 KILOMETER = 1000 METERS 100 CENTIMETERS = 1 METER 1000 MILLIMETERS = 1 METER 1,000,000 MICROMETERS = 1 METER

17. MASS THE AMOUNT OF MATTER IN A SAMPLE MEASURED IN THE SI UNIT OF KILOGRAM 1 MEGAGRAM = 1,000,000 GRAMS 1 KILOGRAM = 1000 GRAMS 100 CENTIGRAMS = 1 GRAM 1000 MILLIGRAMS = 1 GRAM 1,000,000 MICROGRAMS = 1 GRAM

18. VOLUME THE AMOUNT OF SPACE TAKEN UP BY A SAMPLE MEASURED IN SI UNITS OF LITERS 1 MEGALITER = 1,000,000 LITERS 1 KILOLITER = 1000 LITERS 100 CENTILITERS = 1 LITER 1000 MILLILITERS = 1 LITER 1,000,000 MICROLITERS = 1 LITER

19. COMPUTER LANGUAGE

20. METRIC PREFIXES WHAT IS CONVENIENT IS THAT THE PREFIX INDICATES MAGNITUDE WHICH DOES NOT DEPEND UPON WHAT IS BEING MEASURED FOR EXAMPLE, GIGA MEANS A BILLION OR 1,000,000,000 OR 10 9 WHETHER IT IS A GIGABYTE, GIGAGRAM, GIGASECOND, GIGALITER, OR GIGAMETER. THE MAGNITUDE IS THE SAME, THE BASE UNIT REFLECTS WHETHER IT IS A MASS, VOLUME, TIME, COMPUTER STORAGE, OR DISTANCE MEASUREMENT.