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Warm-Up !

1. Match the unit on the left with the value on the right. a. Milli- 1. 1000x b. Kilo - 2. 0.10x c. Centi - 3. 0.001x d. Deci- 4. 0.01x 2. Name the metric unit most appropriate for measuring: A. Mass of a penny d. Volume of Pepsi B. Distance to Tahoe e. Your mass

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Warm-Up !

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  1. 1. Match the unit on the left with the value on the right. a. Milli- 1. 1000x b. Kilo - 2. 0.10x c. Centi - 3. 0.001x d. Deci- 4. 0.01x 2. Name the metric unit most appropriate for measuring: A. Mass of a penny d. Volume of Pepsi B. Distance to Tahoe e. Your mass C. Length of your shoe f. Temperature of your coffee 3. a) You have a gold ring with a volume of 0.75 cm3. Given that the density of gold is 19.31 g/cm3, what is the mass of that gold? b) If gold is worth $900 per ounce, how much is your ring worth? (0.040 ounce/gram) Warm-Up!

  2. Test Your Metric Knowledge 1. A gram is about the weight of: (a) _____ an apple (b) _____ a dime (c) _____ a pineapple 2. A meter is about the height of: (a) _____ a door (b) _____ a kitchen counter, or a doorknob (c) _____ the seat of a chair 3. Water freezes and boils at: (a) _____ 32 °C and 212 °C (b) _____ 100 °C and 200 °C (c) _____ 0 °C and 100 °C 4. A coffee cup holds about (a) _____ 2 milliliters (mL) (b) _____ 20 mL (c) _____ 250 mL 5. A newborn baby weighs about: (a) _____ 3 kilograms (kg) (b) _____ 30 kg (c) _____ 300 kg 6. The height of a tall man is about: (a) _____ 20 centimeters (cm) (b) _____ 200 cm (c) _____ 2000 cm 7. Normal body temperature is: (a) _____ 25 °C (degrees Celsius) (b) _____ 37 °C (c) _____ 45 °C 8. A liter of milk is: (a) _____ larger than a quart (b) _____ smaller than a quart (c) _____ the same size as a quart 9. A liter of water weighs: (a) _____ 1000 grams (g) (b) _____ 20 g (c) _____ 100 g 10. The thickness of a dime is about: (a) _____ 0.1 millimeters (mm) (b) _____ 1 mm (c) _____ 5 mm

  3. Answers: 1. b 2. b 3. c 4. c 5. a 6. b7. b 8. a 9. a 10. b

  4. Why is measurement important?

  5. Units of Measurement 2.1 (pages 25 – 30) • A. Why the Metric System? • National Metric Week: Oct. 9 - 15, 2011 • (10th month and the week containing the 10th day)

  6. B. Base Units of the SI System Based on an object or event of the physical world Independent of other units Second s Meter m Kilogram kg Kelvin K Mole mol Ampere A Candela cd

  7. C. Derived Units Combination ____________________ of base units üVolume cm3 (solids) or ml (liquids) üDensity g/cm3 (solids) or g/ml (liquids) You need your calculator

  8. Goal: Determine the largest amt of sand that can be added to a film canister so that it can still float in a container of water. What to do: Obtain a film canister and ruler. Calculate total mass needed for floating (water has a density of 1 g/cm3) Add sand to container to get to obtain desired mass Bring film canister w/ sand to Ms. Buchanan for testing If it floats (without tipping over) – you get 10 lab pts! You can buy a hint for 2 pts. If it sinks or tips, you get 5 pts. Highest mass that floats – 5 xc points! Second highest mass that floats – 3 xc points! Density Challenge!

  9. D. Temperature Scale Celsius Scale Water Freezes ________ Water Boils: __________ 0ºC 100ºC Kelvin Scale: (add 273 to ºCelsius) Water Freezes_______ Water Boils:________ 273K 373K

  10. II. Scientific Notation & Dimensional Analysis A. Scientific Notation 1. Handling numbers: • in a gram of Hydrogen there are 602,214,000,000,000,000,000,000 atoms • distance between particles in a salt crystal is 0.000 000 002 814 cm • add 0.000 000 000 036 + 0.000 000 000 000 046 = ? Easier to use scientific notation M x 10n M = between 1 & 10 n = integer (1, 2, 3...)

  11. Examples: (from above) 1) 6.02214x1023 2) 2.814x10-9 3) 3.6x10-11 + 4.6x10-14 = ? 3.6046 x 10-11

  12. Try a few! 4) 6.3x104 + 3.9x103 =? 5) (8.0x104) (5.0x102) =? 6) 6.0x107 9.0x105 7) 3.0x10-8 5.0x109 6.69 x 104 4.0 x 107 6.7 x 101 = = 6.0 x 10-18

  13. Estimate how far the winning jump was in feet.

  14. 100cm1m 1 inch 2.54 cm 1 ft 12 in 7.15 m X X X J. Faklaris = = 23.5 feet

  15. D. Dimensional Analysis (aka Factor label) p. 34-35 • Activity Directions: • Table groups, take the cards out of your envelope. • Find the card showing the island and people. How many people live on the island? • Now find a card with a person and a house. • How many houses are on the island? • How many dogs are on the island? • How many cats are on the island? • How many pine trees are on the island?

  16. 3ft 1yd 12 in 1 ft 2.54 cm 1 in 1 m 100 cm 2. Examples – without the cards! a. How many meters in a one hundred yard dash? 1inch = 2.54 cm = 91.4m 100 yds X X X X ? m

  17. b. How many kg in a 4.00 ounce McDonald's hamburger? 1kg = 1000g 16 ounces = 1 pound 1 pound = 454 grams 0.114 kg

  18. c. If Shaq is 7'2" tall how many millimeters tall is he? 1 inch = 2.54 cm 2184 mm

  19. d. Convert 8 wags to warps. 1 wag = 12 zooms 1000 warps = 1bam 3 zoom = 1 bam 32,000 warps

  20. e. A computer switch switches 60 times in a microsecond, how many times does it switch in a minute? 1,000,000 microsecond = 1 sec 3.6 x 109 switches in a minute

  21. f. How many milliliters in a 12 fl oz can of soda? 1000ml = 1L, 1L = 1.06 quarts, 4 quarts = 1 gal, 1gal = 128 fluid oz. 354 mL

  22. Calculate the time required for a student aide to earn $567 at $9.00 per hour. Answer – 63.0 hours How many square feet are in 6.60 square yards? Answer: 59.4 ft2 Change 15 mph to feet per second. Answer = 22 feet per second Warm-Up – Dimensional Analysis

  23. III. How Reliable are Measurements? Accuracy vs Precision

  24. III. How Reliable are Measurements? • precision – how close a series of measurements are to one another; reliability or reproducibility Usually reported as +/- 1 of the estimated unit or by looking at the deviation of the data from the mean (absolute, or standard deviation). • accuracy - how a measured value is to an accepted value – reported as % error • % error = observed value - true value x 100 • true value

  25. Everyone write down a measurement for the width of your note sheet. Please use centimeters and estimate to the nearest 0.05 cm. Write down the measurements taken by yourself and 4 others near you. Determine your average measurement (mean). Calculate your accuracy (% error) given that the “True” value (according to Ms. B) is 21.55 cm. Now determine your precision. Find the /deviation/ of each measurement as compared to the mean. Average these deviations. This is your +/- precision. Record as: Average +/- average deviation. Honors: Determine Standard Deviation Practice w/ Measurement

  26. 2 3 4 Place holder Rules for Significant Figures (sig figs)pgs. 39-42 **1. Definition: Any number that is measured 2. zeros that act as place holders are not significant ex:. 3 cm = 0.03 m _____ sig fig 3. All final zeros to the right of the decimal place and arise as a part of a measurement are significant ex:0.0005030 _____ sig fig ex: 600? use scientific notation   6.00x 102 = ______ sig fig 6.0 x 102 = _____ sig fig   6 x 102 =_____ sig fig Include all known values, plus one estimated value 1 4 1 3 2 1

  27. 4. Non-zero measurements are always significant 5. Zeros between non-zero numbers are always significant

  28. 6. At times the answer to a calculation contains more figures than are significant ex: 3.6247 3 sig fig = 3.62 7.5647 4 sig fig = __________ 6.2501 2 sig fig = __________ 3.250 2 sig fig = __________ 7.635 3 sig fig = __________ 8.105 3 sig fig = __________ • Rounding: • If less than 5, drop it and all figures to the right. • If it is more than 5, increase the number to be rounded by one • If it is 5, and followed by nonzero digit round up • If it is 5, look at the figure to be rounded • Even #, drop 5 and figures that follow • Odd #, round up 7.565 6.3 3.2 7.64 8.10

  29. 7. The result of an addition or subtraction should be reported to the same number of decimal places as that of the term with the least number of decimal places. ex: 1611.032 5.6 + 32.4524 1649.0844? =1649.1

  30. 8. The answer to a multiplication or division problem is rounded off to the same number of sig fig as is possessed by the term having the fewest significant figures used in the calculation. ex: 152.06 x 0.24 = 36.4944? = 36

  31. Based on the data given which day received the most rain? How might this data be better organized?

  32. The End

  33. Review of Scientific Notation I. 1. 7.42 x 102 3. 6.54000 x 101 2. 4.6 x 10-2 4. 5.287000 x 102 II. 6. 60 000 9. 0.0005280 7. 0.093 10. 100.0 8. 6.4 11. 88,000 III. 12. 8.8 x 103 16. 9 x 102 13. 1.9 x 104 17. 1.1 x 108 14. 5.7 x 10-3 18. 9.99 x 10-1 15. 3.6 x 10-3 19. 2.5 x 10-4 HW Answers – Sci. Not. & Dim. Analysis

  34. 1. 4,741 km 2. 7.265 L 3. 0.93 mi 4. 0.918 g 5. 2.40 mL 6. 8 servings 7. 27.8 m/s 8. 7.99 g/mL 9. 6.25 x 106 kg 10 – 0.0964 mm HW: Dimensional Analysis Practice Problems

  35. 1a) 2 b) 3 c) 3 d) 2 e) 2 f) 3 g) 2 h) 4 a) 5.57 x 102 b) 6.4 x 10-2 c) 4.3 x 103 d) 3.820 x 102 e) 1.18 x 107 f) 7 x 10-3 a) 17.9 (3) b) 38.4 (3) c) 66 (2) d) 3.99 (3) e) 1.89 (3) f) 0.017 (2) g) 7.3 (2) h) 42 (2) a) 3.4 x 105 b) 1.67 x 102 c) 1.7 x 106 d) 1.4 x 10-4 e) 4.4 x 10-2 a) 134.6 b) 695.7 c) 1.38 x 1012 d) 1.7 x 104 e) 1.48 x 10-9 Significant Figures and Exponential Notation

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