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Measurement & CalculationAn IntroductionScientific Inquiry: What it is & What it is not!Scientific Thinking ProcessCommunicatingSilent, oral, written, pictorialObserving Seeing, hearing, feeling, tasting, smellingComparing Sensory comparisons, relative position comparisons; measurement (linear, volume, mass, quantity, temperature)OrganizingCategorizing, grouping, classifyingOrdering: seriating and sequencingRelatingCause and effect relationships; space/timerelationships; controlled experimentationInferringPredicting patterns based on dataformulating models; theorizingApplying Using knowledge to solve complex problems; inventingScientific InquiryForm HypothesisGather data-observable; measurable; replicableDesign experimentUse technology to investigate-weigh, calculateAnalyze and describe data-statistical; graphEvaluate accuracy and precision of dataRevise scientific explanation or model-using logic and evidenceCommunicate and defend Example- Which Shampoo to use?Question: Is Suave shampoo the best?

Hypothesis: Which shampoo cleans the best? (leaves least residue)Gather data: Buy shampoosDesign experiment: Determine test-hair or fabric or glassSet up & perform experiment: Use 3 glasses; Wash- #1-with water only #2-Suave #3-AdidasEvaluate: Compare glassware immediately; later; Retest-compareCommunicate: Tell others! Analyze was the difference significant Scientific Method: logical approach to solving problems by observing and collecting data, formulating hypotheses, testing hypotheses, and formulating theories that are supported by data.

Hypothesis: testable statement which makes predictions

Model: Physical object that explains how a phenomena occurs and how data or events are related.

Theory: Broad generalization that explains a body of facts or phenomena

Scientific InquiryEarth is center of universeClaudis PtolemySun is center of UniverseNicolas Copernicus

A.D. 1501543PsuedoscienceFake science that has no tests for its validity.PhrenologyAstrology- HoroscopesSuperstition

Which are testable hypotheses?1. Topeka West football team is #1 in 5A Division.2. The Topeka West band has the best uniforms.3. Taco Johns tacos are the best price in Topeka.4. American Eagle jeans fit better than Old Navy jeans.5. Nicolas Coperinus was first to publish a heliocentric modelfor the universe.6. Meterologists use weather balloons to study the upper atmosphere.

Which are scientific laws/principle?Scientific Law: A general hypothesis/statement about the relationship of natural quantities that has been proven over & over again.Matter is neither created nor destroyed; simply interchanged.Every object remains at rest or in at continual motion until another force is acted on it.The position of the Milky Way Galaxy will remain constant.Measurement Mania!Does size matter REALLY?!!

Quantity: Something that has magnitude, size, or amountWhat items require exact measurement to you?SI Measurement:Le Systeme International dUnitesBase UnitsLength- mmetermMasskgkilogramkgTimetsecondsTemperatureTKelvinKAmount of substancenmolemolElectric current lampereALuminous intensity IvcandelacdSI Prefixes

Can you see estimate these sizes?How many meters tall is Michael Beasley? How many centimeters tall is Beasley?Can you convert between units?

He is 68 tall. There are 39 in a meter. There are 12 in a foot.The answer: He is 80 tall which is 2.02 meters. How many cm?Weight vs. MassWhat the difference between weight & mass?

Picture of Earth & Moon as seen from Mars!Weight- measure of the gravitational pull on matterMass- measure of the quantity of matter in a substanceDerived SI UnitsDerived units are combinations of the SI base quantities. Volume is the amount of space occupied by a substance.Some combination units have their own name:Heat measurement: Joule= force x lengthnewton * mPressure measurement:Pascal=Pa= force/areanewton/m2 = kg/m * s2

Derived units- great for applications! QuantitySymbolUnitDerivationAreaAm2length x widthVolumeVm3 length x width x heightDensityD kg/m3 mass/volumeMolar massM kg/molmass/amt of sub.Concentrationc mol/Lamt of sub./volumeMolar volumeV m3/molvolume/amt of sub.EnergyE Jouleforce x length

Note: mol = mole

Breakdown of derived unitsArea= length x width2 cm8 cmVolume = length x width x height4 m6 m2 mDensity = mass/volume4 m2 m6 m24 kg2 cm x 8 cm = 16 cm 24m x 2m x 6m=48 m3 24 kg = 0.5 kg/m3 4m x 2m x 6m

Molar mass = mass amt. of sub.

Concentration= Amt. of subvolume8 kg4 moles of NaCl3 moles Co

1000 mlMolar Volume= volumeamt of substance

0.4 molescaffeine0.4 L8 kg = 2 kg4 mol mol3 mol = 3 mol1 LL0.4 L = 1 L0.4 mol molDensity Its your destiny!Density= Mass VolumeVolume= Mass Mass = (Density) * (Volume) Densityhttp://www.youtube.com/watch?v=14nahP_FVnMWhat are things you convert daily?

Conversion Units

1 dozen donuts = 12 donuts

If I had 3 dozen donuts, how many donuts do I have?3 dozen| 12 donuts = 36 donuts1 dozenIf I had 48 donuts, how many dozen donuts do I have?48 donuts|1 dozen=4 dozen donuts 12 donutsConversion FactorsA conversion factor is a ratio derived from the equality between two different units that can be used to convert from one unit to the other.Always go back to the units you know wellUse LOGIC!1 m = 100 cm = 0.001 km How many km is it to KU if you are 7800 m away?1 L = 1000 ml = 100 clHow many ml are in 6.2 L of Mt. Dew?1 kg = 1000 g = 1,000,000 mg How many g are in 500,000 mg?7.8km6200 ml500 gAccuracy & PrecisionAccuracy refers to the closeness of measurements to the correct or accepted value of the quantity measured.Precision refers to the closeness of a set of measurements of the same quantity made in the same way.

What was your error in your last prediction? Percent error is calculated by subtracting the e xperimental value from the accepted value, dividing the difference by the accepted value, and then multiplying by 100.Percent Error = Valueaccepted Valueexperimental x 100ValueacceptedName some predictions-

Significant Figureshttp://www.youtube.com/watch?v=9PeVHnjqbBcSignificant Figures- numbers in a measurement consist of all the digits known with certainty plus one final digit, which is somewhat uncertain or is estimated.Rules on Significant Figures-Non-zero numbers are significant (83.45)Captured zeros are significant.(bordered by nonzero numbers- like 703)Trailing zeros are significant IF there is a decimal (2.60; 400; 401.)Leading zeros are never significant (00.016)

Identify the number of significant figures:1) 3.08002) 0.004183) 7.09 x 1054) 91,6005) 0.0030056) 3.200 x 1097) 2508) 780,000,0009) 0.010110) 0.008001)511) 13.01 + 10.1 = a. 23b. 23.1c. 23.1112) 20.5 6.33 =a. 15b. 14.2c. 14.2313) 22.1 + 14.2 =a. 30b. 36c. 36.314) 1.5 x 2 =a. 3b. 3.0c. 3.0011) b.2)33)34)35)46)47)28)29)310)312)b13)c14)aSig Figs in action!Addition & SubtractionMultiplication & DivisionWhen adding or subtracting decimals, the answer must have the same number of digits to the right of the decimal point as there are in the measurement having the fewest digits to the right of the decimal point.Ex. 13.55 4.3 = 9.25 = 9.3 (round)Whole numbers should be rounded so that the answers final digit should be rounded the same as that of the leftmost uncertain digit regardless of the number of places.http://www.youtube.com/watch?v=5UjwJ9PIUvE&feature=related

First determine the significant figures of the numbers of the problem. The least significant figure determines the number of significant figures in the product or quotient.

Ex. 237/6 = 39.5 = 40Significant Figures PracticeAddition/subtraction- when adding or subtracting decimals, the answer must have the same places as the least significant figure. You cannot produce a more accurate number than you started!

Ex. 6.32 g8.0 g+ 1.2 g - 7.2 gMultiplication/divisionThe answer can have no more significant figures than are in the measurement with the fewest number of significant figures.

Ex. 1.10 mm x 6.0 mm = 7.5 g 0.8 g7.0 mm2 because 6.60 mm2 is more precise than our measurements indicate.Scientific NotationScientific Notation- numbers are written in the form M x 10n, where the factor M is a number greater than or equal to 1 but less than 10 and n is a whole number.

3,400 m = 3.4 x 103 m .0034 m = 3.4 x 10-3 m

In addition, exponents (n) must be equivalentIn multiplication, exponents (n) are added.In division, exponents (n) are subtracted.Guided Practice of Scientific NotationAddition/Subtraction5.2 x 106 L9.3 x 10-4 J + 3.1 x 106 L - 7.1 x 10-4 J 8.3 x 106 L2.2 x 10-4 J

Multiplication/Division (9.0 x 104 m)(6.0 x 102m)54 x 106 m25.4 x 107m236 x 10-3 m /6.0 x 106 s6 x 10-9 m/sProportionalityDirect Proportional- 2 quantities are directly proportional to each other if dividing one by the other gives a constant valuey = kX

Inverse Proportionality-2 quantities if their product is constantExample: xy = k