REFORMS SUMMER INSTITUTE AUGUST 10-21, 2009 Part 1:Pace and Compass Mapping Part 2:Scientific Measurement and Reporting Scientific Data Silt & Clay Particle Size 30.00 % 20.00 10.00 0.00 Warren County Forest: Site 1C 0-5cm 5-10cm 10-20cm 20-25cm Dr. Marty Becker and Dr. Jennifer Callanan Science Hall 450 and 448 beckerm2@wpunj.edu callananj@wpunj.edu Exercise 1: Drawing a Pace and Compass Map Perhaps the most simplistic of all maps is the Pace and Compass Map. These types of maps have been used for centuries by explorers, navigators, surveyors and property owners. Pace and Compass Maps represent distance and direction and like all maps, have some type of scale. The scale converts true earth distance to distance on the map. How to Draw a Pace and Compass Map: Using the sheet provided, create a pace and compass map of the following set of data below. To create an accurate map of the property, use a protractor and ruler. No lines should be drawn freehand. Make north the top of with the paper oriented in portrait view. Begin your map by placing a starting dot 7 centimeters from the bottom and 4 centimeters from the left edge. The scale for the map is 1cm = 10 feet plotting all legs in sequence. You should almost end up back where you started if you plot the points carefully. (Any minor errors in measuring distance and direction on your map of the data become cumulative in this exercise). Details: A surveyor purchased a piece of property and wanted to create a Pace and Compass Map of the property for tax purposes. The surveyor had a pace of 5 feet and a Brunton compass. Pace is the average distance between successive strides while walking. A Brunton compass is a precision compass utilized for surveying and measuring the orientation of geologic features. Using the surveyor’s pace and a Brunton compass, the following data was collected: Leg Number of Paces Direction 1. 18.4 N 90 E 2. 15 N 40 E 3. 12.8 Due N 4. 15.4 N 50 W 5. 25.4 S 40 W 6. 15.4 Due S Actual Distance (in Feet) Scale Distance (in Centimeters) A. Convert the number of paces into Actual Distance using a pace of 5 feet per pace. B. Convert the Actual Distance into Centimeters using a scale of Scale 1 cm=10 ft. C. Carefully plot the Pace and Compass Map on the next page. N Exercise 1: Pace and Compass Map. Please draw map below. ↑ Scale 1 cm=10 ft. Extension Questions: 1) What is the perimeter of the property? (Add up all the leg lengths in centimeters and convert to actual distance in feet). 2) Divide the property up into squares and triangles by drawing straight lines on the Pace and Compass map you created. There are a number of different ways this can be done. No lines should be drawn freehand. 3) The area of a square= length X width. The area of a triangle=1/2 base X height **Determine the area for all the squares and triangles you have drawn. Please show work here: 4) To determine the area of the surveyor’s property add up the areas of the triangles and squares you have drawn. Please show work here: 5) Extra Credit: 1 acre= 43,560 square feet. How many acres did the surveyor purchase? Please show work here: Exercise 2: Creating Your Own Pace and Compass Map We will now gather data similar to Exercise 1 at a selected on campus location and create our own Pace and Compass Map. Materials: 1. Graph paper and clip board 2. Calculator, pen, ruler and protractor 3. Yellow caution tape 4. Tape measure 5. Compass In order to do collect the necessary data: we need to 1) establish your average pace; and 2) learn how to take a bearing with a compass. To establish your average pace: 1. Roll out 100 feet of a tape measure on a flat surface. 2. Utilizing your average walking stride, count the number of strides it takes to walk the 100 feet length. 3. Divide the 100 foot length by the number of strides to determine the number of feet per stride. For example, if you take 20 strides to walk the 100 foot length your pace would be 5 feet per stride. This would be a good approximate pace for someone who was 6 feet tall. 4. Repeat this process two additional times and take the average of the three determined pace measurements. This will be your pace for the exercise. How to take a bearing with a compass: 1. Make sure you are not wearing any metal. For example, your belt buckle will alter a compass reading. 2. Adjust the Bruton compass for the magnetic declination of your area. I will explain this in class and help you with this adjustment. 3. Holding the compass near your waist and from a starting point, align your compass mirror and sighting arm with the object you wish to take a bearing on. 4. Use the leveling bubble to make sure the compass is level and make sure you can see the object you are taking a bearing on as a straight line across the sighting arm and in the mirror across the center line. 5. Read the white needle for the bearing. Many people prefer to take these types of bearing in terms of quadrants by dividing the compass up into 4 areas of 90 degrees each. 6. These bearing will be specified as North X degrees East or West or South X degrees East or West. 7. Like anything else, taking accurate and precise bearing takes practice. Part A: Collect the data to create a Pace and Compass map of the designated area. 1. Yellow caution tape has been tied around a selected group of trees and rocks that delineates the area to be mapped. 2. Select a starting point and take a bearing to the first tree or rock. Allow your group partner(s) to also take this bearing to confirm your reading. Record this bearing in the table provided. 3. Carefully pace off the distance between your starting point and the tree or rock you took a bearing on. Have your group partner (s) also pace this off. Utilizing your pace, calculate the distance between the starting point and the tree or rock you took a bearing on. (Be aware that your group partner(s) pace may be different than yours in the calculation of actual distance). Record this distance in the table provided. 4. Repeat this process in sequence for all the individual “legs” that delineate the property boundary. Record the data in the table provided. 5. Convert your actual distance between the trees or rocks to map scale distance. We will use a scale of 1cm = 10 feet. This is the same scale utilized for exercise one. This will allow the map to be plotted on a standard piece of paper. Leg Number of Paces Bearing Actual Distance (number of paces X distance per pace) Map Scale Distance 1 2 3 4 5 6 7 Part B: Utilizing the same techniques and procedures explained in Exercise 1, plot a map of the area for which the data was collected. N Exercise 2: Pace and Compass Map. Please draw map below. ↑ Scale 1 cm=10 ft Exercise 3: The Pirate’s Treasure Map A Pirate’s Treasure Map can be created utilizing the same techniques and skills from Exercises 1 and 2. These exercise are simply worked in reverse where you start with a Pace and Compass Map and utilize the bearings and distances between selected objects to discover a buried treasure. In addition to the materials listed in exercise 1, a small treasure chest with some chocolate coins will serve as the “prize” for being able to read and recreate a Pace and Compass map. Part A: Procedure 1) Carefully create a Pace and Compass Map to serve as the Pirate’s Treasure map. (For the purposes of this exercise, I will provide you with the treasure map). 2) Select stationary objects that are not likely to move such as large trees or rocks. 3) The Pirate’s Treasure map does not have to end at a starting point. 4) At the end of the last leg, bury the small treasure chest with chocolate coins. 5) Discovery of the treasure chest allows all the “pirates” to eat the chocolate coins. Bearing Actual Leg Number of Feet number of paces 1 42 S16°W 2 26 S58°W 3 46 N78°W 4 69 S56°W 5 37 S41°E Extension Questions: 1) What problems may occur to the accuracy and precision of a Pirate’s Treasure map over time? 2) How could you design a method to check the accuracy and precision of the Pirate’s Treasure map? Please explain by drawing a diagram. (Hint: could objects near the buried treasure also serve as bearing points of distance and direction?) 3) If the Pirate’s Treasure map were ever stolen or fell into the wrong hands, how could a smart pirate always protect the secret location of the buried treasure? Be specific. Applying Exercises 1–3 to your classroom ***Any of these exercises can be tailored for a 3-8th grade audience. Skill Sets: Multiple skill sets are utilized for these exercises and represent an excellent integration of math and science. Skills in these three exercises are “progressive” and rely on mastery of earlier techniques. Some include: a) Measurement basics with ruler, protractor and compass b) Conversion between units of measurement c) Accuracy and Precision d) Map Scale e) Graphical representation of actual Earth Surface f) Compass utilization basics g) Basic surveyor skills Applicability to the NJCCSS: These exercises can be readily correlated to the following NJCCSS. Examples of some NJCCSS that apply to Pace and Compass Mapping include: K–8: 5.1A, B (Scientific Process-Habits of the Mind, Inquiry and Problem Solving) K–8: 5.2 B (Science and Society-Historical Perspectives) K–8: 5.3A, B, D (Mathematical Applications-Numerical Operations, Geometry and Measurement, Data Analysis and Probability) K–8: 5.4 B, C (Nature and Process of Technology-Nature of Technology and Technological Design) 3–8: 5.8 D (Earth Science: How we study the Earth) Assessment: 1. Grading these exercises is an easy process. An example: a) For Exercise 1: Carefully draw the pace and compass map from the data on an overhead transparency. This can serve as your grading instrument. b) Compare the individual bearings to your overlay. Each degree off for the individual bearings is assigned a deduction. Add up the total number of degrees off for all of the bearings. (Example: each 5 degrees off equals the loss of 1 point). c) Compare the distance of individual bearings to your overlay. Each centimeter between the end point of a leg on the overhead and drawn map is assigned a deduction. (Example: each 5 degrees off equals the loss of 1 point). d) Closure Error: Because of the nature of the instruments utilized to make a pace and compass map, it is very easy to be a few degrees off on a bearing or a few feet off on a distance. Errors also occur when these measurements are converted to map distance and plotted with a ruler and protractor. It would be near impossible based on cumulative errors to end up where you have started when the map is drawn. The distance between where you start the map and where the last leg of the map ends is called “closure error.” Establish a deduction for the closure error. (Example: each 1 centimeter distance between the starting and fishing points equals the loss of one point). e) For Exercise 2: Carefully draw the pace and compass map on an overhead transparency. Errors in the bearing part of the exercise can be reduced by having a number of faculty or students that are skilled with the compass take the individual bearings. Take the average bearing as the accepted bearing for the purposes of grading. Errors in the distance part of the exercise can be greatly reduced by simply using the tape measure to determine the distance between the individual trees and rocks. f) Grading the exercise is the same as Exercise 1 where deductions are taken for deviations of bearings and distances when compared to the transparency. g) For Exercise 3: The reward of finding the buried Treasure is an indicator of mastery of pace and compass mapping skills. Additional Notes: Exercise 4: Density by Direct Measurement of Volume Materials: Funsize Snickers Funsize 3-Musketeers Ruler (metric) Scale or Digital Balance (metric) Calculator (optional) Large plastic cup Water The density of an object is defined as its mass per unit volume. This can be represented ρ = m/ V by the equation: “It would break my heart if you forgot this formula.” where: ρ is the density, m is the mass, V is the volume. Mass is defined as the property of a body that causes it to have weight in a gravitational field. Volume is defined as the amount of 3-dimensional space occupied by an object. Consider This! Objects that are the same size, or occupy the same volume, may not have the same density. We can illustrate this with the following experiment whereby we determine density by direct measurement of volume. Experiment: For each candy bar, measure, in centimeters (cm), the length (l), width(w), and height (h) and record the measurements in the chart below. Calculate the volume of each candy bar using the equation: V=lxwxh Record the measurements in the chart. M V Candy bar Length Width Height VOLUME (cm) (cm) (cm) (cm3) Snickers 3 Musketeers How does the volume of each candy bar compare? Determine the mass, in grams, of each of the candy bars by using the digital balance and record the measurements in the chart. Candy bar Mass (g) Snickers 3 Musketeers How does the mass of each candy bar compare? Now that you have determined the volume and the mass for each candy bar, you can calculate their density. Use the following equation to calculate the density, in g/cm3, of each candy bar and record your measurements in the chart. ρ = m/ V Candy bar Density (g/cm3) Snickers 3 Musketeers How does the density of each candy bar compare? Remember! Density is the ratio of weight compared to volume…it’s not just the weight nor is it just the size (volume). Materials of the same volume, with differing densities, will react differently when placed in water. Fill the 2 cups each 2/3 full with water. Drop the Snickers in one cup and the 3 Musketeers in the other cup. Describe what happens. Additional Math: Have students convert the Volume, Mass, and Density measurements to other units. Conversion Factors: Multiply by To change To acres hectares acres square feet acres square miles atmospheres cms. of mercury Btu kilowatt-hour Btu/hour watts bushels cubic inches bushels (U.S.) hectoliters .3524 centimeters inches .3937 centimeters feet cubic feet cubic meters cubic meters cubic feet cubic meters cubic yards cubic yards cubic meters degrees radians .01745 dynes grams .00102 fathoms feet feet meters feet miles (nautical) .4047 43,560 .001562 76 .0002931 .2931 2150.4 .03281 .0283 35.3145 1.3079 .7646 6.0 .3048 .0001645 feet miles (statute) .0001894 feet/second miles/hour gallons (U.S.) liters grains grams .0648 grams grains 15.4324 grams ounces (avdp) grams pounds hectares acres 2.4710 hectoliters bushels (U.S.) 2.8378 horsepower watts 745.7 horsepower Btu/hour 2,547 hours days inches millimeters 25.4000 inches centimeters 2.5400 kilograms pounds (avdp or troy) 2.2046 kilometers miles .6214 kilowatt-hour Btu 3412 knots nautical miles/hour knots statute miles/hour 1.151 liters gallons (U.S.) .2642 liters pecks .1135 liters pints (dry) .6818 3.7853 .0353 .002205 .04167 1.0 1.8162 liters pints (liquid) 2.1134 liters quarts (dry) .9081 liters quarts (liquid) 1.0567 meters feet 3.2808 meters miles .0006214 meters yards 1.0936 metric tons tons (long) .9842 metric tons tons (short) 1.1023 miles kilometers 1.6093 miles feet miles (nautical) miles (statute) 1.1516 miles (statute) miles (nautical) .8684 miles/hour feet/minute millimeters inches .0394 ounces (avdp) grams 28.3495 ounces pounds ounces (troy) ounces (avdp) pints (dry) liters .5506 pints (liquid) liters .4732 5280 88 .0625 1.09714 pounds (ap or troy) kilograms .3732 pounds (avdp) kilograms .4536 pounds ounces quarts (dry) liters 1.1012 quarts (liquid) liters .9463 radians degrees 57.30 square feet square meters .0929 square kilometers square miles .3861 square meters square feet square meters square yards 1.1960 square miles square kilometers 2.5900 square yards square meters .8361 tons (long) metric tons 1.016 tons (short) metric tons .9072 tons (long) pounds 2240 tons (short) pounds 2000 yards meters .9144 yards miles 16 10.7639 .0005682 Exercise 5: Density by Archimedes’ Principle Materials: Aluminum Cube Beam Balance Graduated Cyliner Water Calculator (optional) Eureka! The density of an object can be measured in 2 ways: 1. Direct measurement of volume 2. Archimedes’ Principle Archimedes’ Principle states that any object, wholly or partly immersed in a fluid, is buoyed up by a force equal to the weight of the fluid displaced by the object. Buoyancy is the upward force that keeps things afloat. Experiment: Determine the mass, in grams, of the aluminum (Al) cube by using the digital balance and record the measurement in the chart. Record the volume of water, in cm3, in the graduated cylinder (V0) and record your measurement in the chart. Place the Al cube in the graduated cylinder and record the volume of water (V1) in the chart. Calculate the volume of the Al cube with the equation: (VAl = V1– V0) and record the measurement in the chart. Mass Aluminum Cube V0 V1 VAl Calculate the density of the Al cube using the formula ρ = m1/ m2 - m3 ρ = _________ Calculate the density of the Al cube using the method in Exercise 1 with the formula ρ = m1/ V ρ = ________ Consider This! Suppose you had an oddly shaped object. Which method would be better suited for measuring the density? Exercise 6: Experimental Error Materials: Calculator (optional) Experimental Error is defined as the difference between a measurement and the true value or between two measured values. It is measured by accuracy and precision. Two common ways to describe experimental error are by percent error and percent difference. Accuracy measures how close a measured value is to the true/accepted value. Precision (Repeatability/ Reproducibility) measures how closely two or more measurements agree with one another. Percent Error measures the accuracy of a measurement by the difference between a measured value and a true value. Percent Difference measures precision of two measurements by the difference between the measured values as a fraction of the average of two values. Consider This! The true density of aluminum is 2.7 g/cm3. Experiment: Determine the percent error of both your measured densities of the aluminum cube in Exercise 2 using the equation and record your measurements in the chart. % Error = | E – A| x 100 A Where: E = measured/experimental value A = true/accepted value Density (from Ex. 2) % Error Archimedes Principle Direct Measurement of Volume Determine the percent difference of both your measured densities of the aluminum cube in Exercise 2 and those measured by the group next to you using the equation and record your measurements in the chart. % Difference = | E1 – E2| E1 + E2 2 Where: Archimedes Principle Direct Measurement of Volume x 100 E1 = measured/experimental value 1 E2 = measured/experimental value 2 Density Density Group 1 Group 2 % Difference Exercise 7: Significant Figures & Instrument Sophistication Materials: Oak Cube Beam Balance Digital Balance 4-digit Balance Calculator (optional) A Significant Figure refers to the number of figures that are known with some degree of reliability. For example: 13 have 2 significant figures 13.2 has 3 significant figures 13.20 has 4 significant figures The least significant digit in a measurement depends on the smallest unit which can be measured using the measuring instrument. The least significant digit measured by an instrument is a direct indication of the instrument’s sophistication, or in other words, how technologically advanced the instrument is. Remember! When performing mathematical calculations (average, sum, etc.) on measurements, the result should be rounded off as to have the same number of significant figures as in the component with the least number of significant figures. Experiment: Determine the mass in grams of the oak cube using the 3 different types of balances and record your measurements in the chart. Calculate the average mass of the oak cube from the 3 measurements and record your measurement in the chart. Remember! Use the correct number of significant digits. Mass (g) Beam Balance Oak Cube Mass (g) Digital Balance Mass (g) 4-digit Balance Average Mass (g) Exercise 8: FUN Application Density of Gold = 19.32g/cm3 Density of Pyrite = 5.01g/cm3 REAL Golden Ring $19.99 Order yours today! GOLD! Discovered in Paterson, NJ DON’T MISS YOUR CHANCE TO STRIKE IT RICH! Get your MAP to the location of the GOLD NOW! Only 10 maps will be sold. Send a check or money order for $10,000.00 made payable to: Ima Swindler 100 Gold Rush Road Paterson, NJ 07501 Maps will be shipped by postal service within 8-10 business days. Not responsible for lost or stolen maps, inability to read map or find gold, purity of gold or legitimacy of this transaction. Additional Applications: Is a penny made from copper? Density of Copper = 8.96 g/cm3 Is a made from ? Is a nickel really made from nickel? Density of Nickel = 8.91 g/cm3 Does = ? Exercise 9: Meaningful Data Materials: Calculator (optional) Microsoft Excel The chart below contains particle size data for a forest soil in Warren County, NJ. The data was obtained by a process called sieve analysis where sieves of different size mesh (holes in the screen) are nested on top of each other—largest mesh on top, smallest on bottom. The soil is poured into the top of the sieve stack then shaken. The weight of soil particles remaining in each sieve is then measured to produce the chart below. Procedure: Determine the total weight of soil measured at each depth in the sieve analysis by calculating the total (sum) of all the size fractions and record it in the chart. Warren County Forest: Soil Particle Size Data (Site 1C) Phi Size -1 0 1 Depth >2mm gravel 1-2mm very coarse sand 12.01g 39.77g 42.50g 24.99g 4.06g 7.92g 12.16g 11.75g 0-5cm 5-10cm 10-20cm 20-25cm 0.5-1mm 2 0.250.5mm 3 0.1250.25mm 4.5 Tray 0.0625- <0.0625m 0.125mm m coarse sand medium sand fine sand very fine sand silt & clay 10.35g 8.77g 9.64g 10.61g 4.50g 11.7g 5.56g 4.45g 15.20g 8.29g 8.37g 14.56g 9.04g 7.73g 9.56g 15.03g 17.34g 17.88g 18.97g 26.47g The data that has been produced directly from the sieve analysis is not meaningful data. This data can not be easily compared because the total weight of soil being analyzed is different. It’s like comparing apples to oranges. Therefore, the data must be normalized by converting it into percentages. This way, we will compare apples to apples. Determine the percentage of each size fraction at each depth using the following equation and record your results in the chart below: % Particle Size = weightsize fraction weighttotal x 100 Total (g) Warren County Forest: Soil Particle Size Data (Site 1C) Phi Size -1 0 1 Depth >2mm 1-2mm very coarse sand gravel 0.5-1mm 2 0.250.5mm 3 4.5 Tray 0.1250.06250.25mm 0.125mm <0.0625mm coarse sand medium sand fine sand very fine sand silt & clay 0-5cm 5-10cm 10-20cm 20-25cm As a check that the percentage calculations are correct, calculate the total % (sum) of all the size fractions and record it in the chart. The total should equal 100%. Total (%) Consider This! What could you do if you had to process multiple samples such as are shown in the following chart? Warren County Forest: Soil Particle Size Data (All Sites) Phi Size Site 1 - A Site 1 - A Site 1 - A Site 1 - A Site 1 - B Site 1 - B Site 1 - B Site 1 - B Site 1 - C Site 1 - C Site 1 - C Site 1 - C Site 2 - A Site 2 - A Site 2 - A Site 2 - B Site 2 - B Site 2 - B Site 2 - C Site 2 - C Site 2 - C Site 2 - D Site 2 - D Site 2 - D Site 2 - E Site 2 - E Site 2 - F Site 2 - F Site 2 - G Site 2 - G Site 2 - G Site 2 - H Site 2 - H Site 2 - H Site 2 - I Site 3 - A Site 3 - A Site 3 - A Depth 0-10cm 0-5cm 10-20cm 20-25 0-10cm 0-5cm 10-20cm 20-25cm 0-10cm 0-5cm 10-20cm 20-25cm 0-10cm 0-5cm 10-15cm 0-10cm 0-5cm 10-15cm 0-10cm 0-5cm 10-18cm 0-10cm 0-5cm 10-18cm 0-10cm 0-5cm 0-5cm 0-10cm 0-10cm 0-5cm 10-20cm 0-10cm 0-5cm 10-20cm 0-5cm 0-10cm 0-5cm 10-15cm -1 >2mm 34.5 1.63 26.84 34.71 33.63 22.67 17.02 20.04 39.77 12.01 42.5 24.99 29.27 42.18 33.46 39.48 51.07 28.66 29.99 28.37 21.67 46.97 46.56 34 37.21 35.32 52.45 31.09 26.86 33.29 32.28 28.78 37.7 29.34 34.94 46.75 71.45 40.91 0 1 1-2mm 0.5-1mm 7.28 9.35 3.57 8.41 13.29 14.54 12.03 4.59 7.07 17.58 5.22 8.25 9.1 18.37 10.39 13.04 7.92 8.77 4.06 10.35 12.16 9.64 11.75 10.61 10.41 9.04 9.85 8.43 9.36 10.58 9.78 7.59 4.14 4.81 12.97 10.21 12.19 12.91 9.95 11.12 10.88 11.47 9.39 8.8 12.37 10.37 15.47 12.27 12.85 9.92 9.62 8.61 10.42 8.47 14.04 12.12 9.06 10.54 6.51 8.27 10.33 19.75 4.34 9.83 9.93 8.39 10.87 10.43 10.08 8.81 12.76 11.35 10.19 6.07 18.41 15.91 2 3 4.5 Tray Total (g) 0.250.1250.06250.5mm 0.25mm 0.125mm <0.0625mm 5.53 6.06 9.93 27.77 20.96 12.67 10.24 23.06 5.58 13.6 10.2 23.03 5.64 11.14 10.28 20.12 2.9 12.32 9.37 19.67 6.26 12.5 11.39 26.87 19.03 12.15 12.26 21.66 5.99 15.87 15.9 28.03 11.7 8.29 7.73 17.88 4.5 15.2 9.04 17.34 5.56 8.37 9.56 18.97 4.45 14.56 15.03 26.47 3.12 10.86 11.69 28.56 3.37 9.69 8.32 18.85 4.01 11.63 11.68 25.78 7.56 9.13 8.45 21.18 1.97 8.63 10.83 21.15 4.15 13.29 16.09 23.47 3.38 11.68 13.51 26.16 3.68 9.32 9.53 25.56 6.64 14.51 14.88 26.81 3.11 8.65 9.19 23.66 6.25 5.91 5.79 20.26 10.22 7.32 9.45 19.71 3.51 10.35 10.91 26.67 3.26 8.74 8.74 20.61 6.65 6.34 6.53 14.79 3.43 7.4 11.99 24.18 3.82 10.52 10.28 26.54 8.29 99.11 7.45 14.35 6.26 9.4 12.2 16.16 3.79 12.24 10.31 22.26 2.69 10.71 10.15 25.19 3.31 17.09 15.42 30.36 3.29 9.55 8.81 16.34 3 8.08 7.84 15.31 2.27 5.75 4.22 9.69 3.7 7.8 9.77 13.65 Additional Exercises: Have students convert particle size data in mm to other SI units or to United States Customary Units. International System of Units (SI) Information from: http://physics.nist.gov/cuu/Units/units.html The SI is the modern form of the metric system, devised around the number 10, and is the most widely used system of measurement in the world. The United States is one of only 3 countries who have not adopted the SI system as the primary system for recording measurement. However, all scientific data should be reported in SI units. SI was founded on seven base units for seven base quantities, as given in Table 1. Table 1. SI base units SI base unit Base quantity length mass time electric current thermodynamic temperature amount of substance luminous intensity Name meter kilogram second ampere Symbol m kg s A kelvin K mole candela mol cd Prefixes are often added to an SI unit to produce a multiple of the original unit, which are all integer powers of ten. Prefixes are given in the table below. Name Multiples Symbol deca- hecto- kilo- mega- giga- tera- peta- exa- zetta- yottada Factor 100 101 Name Subdivisions Symbol h k M G T P 102 103 106 109 1012 1015 E Z 1018 1021 Y 1024 deci- centi- milli- micro- nano- pico- femto- atto- zepto- yoctod Factor 100 10−1 c m µ n p f 10−2 10−3 10−6 10−9 10−12 10−15 a z 10−18 10−21 y 10−24 Exercise 10: Graphical Presentation of Data Materials: Graph Paper Ruler Microsoft Excel The percentage of particle size information presented in the chart below is meaningful and relates apples to apples. However, it is difficult to compare data between depths from a chart full of numerical values. Graphically displaying the data is a better option for observing variations in data among samples. Warren County Forest: Soil Particle Size Data (Site 1C) Phi Size -1 Depth >2mm 0-5cm 5-10cm 10-20cm 20-25cm gravel 16.57 38.97 39.81 23.17 0 1 2 0.250.5mm 3 0.1250.25mm 4.5 Tray Total (%) 0.0625- <0.0625m 0.125mm m 1-2mm 0.5-1mm very coarse coarse medium very fine sand sand sand fine sand sand silt & clay 5.60 14.28 6.21 20.97 12.47 23.92 7.76 8.59 11.46 8.12 7.57 17.52 11.39 9.03 5.21 7.84 8.95 17.77 10.89 9.84 4.13 13.50 13.93 24.54 100.00 100.00 100.00 100.00 Procedure: Create a bar graph to illustrate the differences in percent silt and clay at each of the four depths on the graph paper provided. Consider This! What could you do if you had to graphically illustrate multiple samples such as were shown in the chart in exercise 1? There are a variety of graph types that can be used to represent data. However, picking the appropriate type of graph for the field of science or the type of data is important. For example: Particle Size Cumulative %: Site 1C Cumulative % Soil Scientists use a particular type of graph called a cumulative percent graph to illustrate particle size distribution. The shape of the curve can tell a soil scientist, very quickly, about the distribution of particle sizes as well as other soil properties such as sorting of particles. 120 100 80 60 40 20 0 0-5cm 5-10cm 10-20cm 20-25cm -1 0 1 2 Phi Size 3 4.5 Tray Additional Exercises: Graphing: Have students explore various types of graphs to represent the data. Silt & Clay Particle Size 30.00 % 20.00 10.00 0.00 Warren County Forest: Site 1C 0-5cm 5-10cm 10-20cm 20-25cm Silt & Clay Particle Size: Site 1C 0-5cm 5-10cm 10-20cm 20-25cm Silt & Clay Particle Size: Site 1C % 30.00 20.00 10.00 0.00 0-5cm 5-10cm 10-20cm Depth 20-25cm Exercise 11: Technology & Data As technology improves and becomes more sophisticated, the data we can obtain becomes more accurate and precise. Often times, large quantities of data are produced, which without the aid of software such as Microsoft Excel, normalization and graphical representation can be quite tedious. For example, the instrument shown in the picture below is called a Malvern Mastersizer 2000. This sophisticated piece of laboratory equipment can measure the particle size distribution of a soil in a matter of minutes and, unlike sieve analysis, can differentiate silt and clay particles up to < 0.02µ! Without this piece of equipment it would take over 8 hours to determine the percentage of clay sized particles in just one sample by older settling techniques. The Mastersizer utilizes a laser diffraction technique where particles pass through a beam of light, scattering the light, where it is detected on a lens. The amount of light scatter relates to the size of the particle. The following chart is an example of a portion of the data that is obtained using the Mastersizer. The data was reported for 67 size fractions ranging from 0.2089ų to 1905.4607ų and is already normalized to percentage. Compare this data to that given in Exercise 1 using the sieve analysis. Note the difference in: Number of Size Fractions Range of Size Fractions Significant Digits Warren County Forest: Soil Particle Size Data: Site 1A Particle Size (ų) 0.2089 0.2399 0.2754 0.3162 0.3631 0.4169 0.4786 0.5495 Depth 0-5cm 5-10cm 10-20cm 20-25cm 0 0 0.0189 0 0.023 0.0337 0.0881 0.0365 0.1244 0.1812 0.2074 0.1956 0.2122 0.3014 0.3037 0.3191 0.2879 0.4079 0.4067 0.4279 0.3665 0.5199 0.5075 0.541 0.4424 0.6296 0.606 0.6508 0.5199 0.7432 0.7076 0.7639 Particle Size (ų) 0.631 0.7244 0.8318 0.955 1.0965 1.2589 1.4454 1.6596 Depth 0-5cm 5-10cm 10-20cm 20-25cm 0.6003 0.8615 0.8128 0.8823 0.6898 0.9932 0.9296 1.0154 0.7903 1.1397 1.0591 1.166 0.9074 1.3081 1.2079 1.3421 1.0401 1.4961 1.3735 1.5415 1.1899 1.7044 1.5564 1.7649 1.3514 1.9242 1.7485 2.0017 1.5216 2.1494 1.944 2.244 Particle Size (ų) 1.9055 2.1878 2.5119 2.884 3.3113 3.8019 4.3652 5.0119 Depth 0-5cm 5-10cm 10-20cm 20-25cm 1.694 2.369 2.133 2.4782 1.8649 2.5758 2.3092 2.6944 2.0302 2.7625 2.4663 2.8832 2.1859 2.9226 2.5989 3.0368 2.3283 3.0509 2.7024 3.149 2.4515 3.1408 2.7715 3.2141 2.5525 3.1887 2.8033 3.2297 2.6276 3.1928 2.7963 3.1962 Particle Size (ų) 5.7544 6.6069 7.5858 8.7096 10 11.4815 13.1826 15.1356 Depth 0-5cm 5-10cm 10-20cm 20-25cm 2.6798 3.1557 2.7529 3.1181 2.7138 3.0859 2.6809 3.0069 2.7403 2.9924 2.5882 2.8728 2.7705 2.8898 2.4885 2.733 2.8173 2.7861 2.3889 2.5952 2.8889 2.6929 2.3007 2.4726 2.9922 2.612 2.2262 2.3663 3.1225 2.5459 2.1685 2.2799 Particle Size (ų) 17.378 19.9526 22.9087 26.3027 30.1995 34.6737 39.8107 45.7088 Depth 0-5cm 5-10cm 10-20cm 20-25cm 3.2724 2.4892 2.1238 2.2088 3.4206 2.4364 2.0879 2.1492 3.5446 2.3775 2.0525 2.0928 3.6151 2.3039 2.01 2.0329 3.608 2.2072 1.9528 1.9618 3.5066 2.0836 1.8766 1.8753 3.3062 1.9325 1.7795 1.771 3.0167 1.7579 1.6635 1.6501 Particle Size (ų) 52.4807 60.256 69.1831 79.4328 Depth 0-5cm 5-10cm 10-20cm 20-25cm 2.6614 1.5684 1.5345 1.5175 2.2706 1.3744 1.4004 1.3802 1.8834 1.1906 1.2725 1.2486 1.5284 1.0273 1.1592 1.1306 Particle Size (ų) 91.2011 104.7129 120.2264 138.0384 1.2365 0.897 1.069 1.0358 1.018 0.8037 1.0034 0.9687 0.8822 0.7514 0.9625 0.9343 0.821 0.7368 0.941 0.9327 158.4893 181.9701 208.9296 239.8833 275.4229 316.2278 363.0781 416.8694 Consider This! How would you go about graphically representing this data? Would you consider graphing it by hand? YOU’RE IN LUCK! Not only might advanced technology provide you with a larger quantity of more accurate and precise data, often times it is equipped with software which will normalize and graphically report it for you! Now isn’t science EASY? Volume (%) Particle Size Distribution 4 3.5 3 2.5 2 1.5 1 0.5 0 0.01 0.1 1 10 100 1000 3000 100 1000 3000 100 1000 3000 100 1000 3000 Particle Size (µm) Pre 1A 0-5cm - Average, Monday, June 22, 2009 1:00:56 PM Particle Size Distribution 3.5 Volume (%) 3 2.5 2 1.5 1 0.5 0 0.01 0.1 1 10 Particle Size (µm) Pre 1A 0-10cm - Average, Monday, June 22, 2009 1:12:57 PM Particle Size Distribution Volume (%) 3 2.5 2 1.5 1 0.5 0 0.01 0.1 1 10 Particle Size (µm) Pre 1A 10-20cm - Average, Monday, June 22, 2009 1:22:38 PM Particle Size Distribution 3.5 Volume (%) 3 2.5 2 1.5 1 0.5 0 0.01 0.1 1 10 Particle Size (µm) Pre 1A 20-25cm - Average, Monday, June 22, 2009 1:33:40 PM Additional Exercises: Ternary Diagrams From the given table of particle size distribution for a sample obtained using data produced by the Mastersizer, have students determine the type of soil represented at each depth using the ternary diagram of soil classification. Depth % clay % silt % sand 0-5cm 8 20 73 5-10cm 10 23 67 10-20cm 9 22 69 20-25cm 10 24 66 Skill Sets Utilized in the Course: Measurements using ruler, beam balance & digital scales Mathematical operations (addition, multiplication, division, percentages, etc.) Use of formulas to calculate measurements Conversions between units of measurement Accuracy, precision, and experimental error Simple graphing Advanced calculations and graphing using Microsoft Excel Comparison of scientific techniques Instrument sophistication Ternary Diagrams Applicability to the NJCCSS: 5.1 Scientific Processes A.3, B.1 (K-4) A.1-3, B.3 (5-8) 5.3 Mathematical Applications A.1, A.3, D.1 (K-4) A.1, D.1, D.4 (5-8) 5.4 Nature and Process of Technology C.1 (3-4) 5.6 Physical Science-Chemistry A.4 (3-4) A.2 (5-6) Assessment: Assessment of the large majority of the Scientific Measurement course can be done by the final answers to the problems as well as evaluation of the mathematical processes the students’ used to obtain their measurements. Assessment of the Fun Application should be based on the student’s ability to evaluate the legitimacy of the advertisement utilizing the basic skills learned in the previous exercises. Assessment of the Reporting Scientific Data course is again based largely on the students’ mathematical calculations and ability to design a simple graph or to utilize the software to create an appropriate graph of data. The activities of both courses are best assessed assigning partial credit for work as students’ may arrive at incorrect measurements due to a mistake in mathematical calculation. Award points for process as well as final answer. Digital Balance, Universal Specific Gravity Kit, and Density Blocks can be purchased at www.wardsci.com