2 History Created during French Revolution in 1790 French King overthrownNational Assembly of France sets up new governmentFrench Academy of Science told to design new system of weights and measuresLavaiosie appointed to head committee
3 History Called Systeme International d’Unitès, Revised periodically or SI - International System of UnitsRevised periodicallyby International Bureau of Weight and Measures
4 Customary Units of Measurement The English Systema collection of functionally unrelated unitsDifficult to convert from one unit to anotherEx. 1 ft = 12 inches = 0.33 yard = 1/5280 milesCustomary Unitslength - inch, foot, yard, mileweight/mass - ounce, poundvolume - teaspoon, cup, quart, gallontemperature - degrees Fahrenheittime - minutes, hours
5 Advantages of Using the Metric System Universal - used everywhereby all scientists to communicateby all industrialized nationsexcept United StatesU.S. loses billions of dollars in trade
6 Advantages of Using the Metric System Simple to useA few base units make up all measurementslength - metermass - gramsvolume - literstemperature – degrees Celsiustime - seconds
7 Advantages of Using the Metric System There is only one unit of measurement for each type of quantityTo simplify things, very small and very large numbers are expressed as multiples of the base unit.Prefixes are used to represent how much smaller or larger the quantity is compared to the base unit.Easy to convert from one unit to anothershift decimal point rightshift decimal point left
8 Advantages of Using the Metric System Same set of prefixes for all unitsGreek - multiples of the basekilo × the basehecto × the basedeka - 10 × the baseLatin - fractions of the basedeci - tenths of the basecenti - hundredths of the basemilli - thousandths of the baseMnemonic: “Kids Have Dropped Over Dead Converting Metrics.”
10 Units of Length Length - the distance between two points standard unit is meter (m)long distances are measured in kmMeasured using a meter stick or ruler
11 Prefixes and Units of Length centimeter - cm1 m = 100 cm1 cm = 1/100th mmillimeter - mm1 m = 1000 mm1 mm = 1/1000th m10 mm = 1 cmmeasures very small lengthskilometer - km1 km = 1000 m1 m = 1/1000th kmmeasures long distances
12 Measuring Mass Mass - the quantity of matter in an object standard unit is gram (g)Measured using a digital scale or triple beam balance
13 Measuring Volume and Capacity Volume - the amount of space occupied by an objectstandard unit is liter (L)1 L = 1000 ml = 1000 cm3 = 1 dm3Measured using a graduated cylinderCapacity - a measure of the volume inside a container
14 Prefixes and Units of Volume Liter - L1 L = 1000 milliliters1 L = 1000 cubic centimeters = 1000 cm3milliliter - mLmeasures small volumes1 mL = 1 cubic centimeter1000 mL = 1 Liter1 mL = 1/1000th literkiloliter - kLmeasures large volumes1 kL = 1000 L
15 Measuring Volume Measured with a graduated cylinder Determine value of each mark on the scaleRead scale using the lowest position of the meniscusMeasure the meniscus at eye level from the center of the meniscus.In the case of water and most liquids, the meniscus is concave. Mercury produces a convex meniscus.
16 Displacement Displacement Amount of water an object replaces Equal to its volume
17 Volume of a Solid, Irregular Object Displacement - amount of water an object replacesProcedurePlace graduate beaker beneath spoutFill the overflow can with water until water begins to spillEmpty the excess waterPlace object to be measured into the overflow canRemove when water stops flowing out of the canMeasure the displaced water using a graduated cylinder.
18 Volume of a Solid, Irregular Object DisplacementCalculate the difference between the initial and final volume measurement.
19 Volume of a Solid, Regular Object Volume - length x width x heightV = 2.8 cm x 3.2 cm x 2.5 cmV = 22.4 cm3Measured with a ruler
20 Calculating DensityDensity - a specific property of matter that is related to its mass divided by the volume.D=M/Vthe ratio of mass to volumeused to characterize a substanceeach substance has a unique densityUnits for density include:g/mLg/cm3g/cc
26 Measurement Unit Conversion You can convert between units of measurementwithin the metric systembetween the English system and metric system
27 Unit ConversionLet your units do the work for you by simply memorizing connections between units.Example: How many donuts are in one dozen?We say: “Twelve donuts in a dozen.”Or: 12 donuts = 1 dozen donutsWhat does any number divided by itself equal?ONE!
28 Unit Conversion This fraction is called a unit factor Multiplication by a unit factor does not change the amount - only the unit.Example: How many donuts are in 3.5 dozen?You can probably do this in your head but try it using the Factor-Label Method.
29 Unit Conversion Rules Start with the given information… Then set up your unit factor…See that the original unit cancels out…Then multiply and divide all numbers…
30 Unit Conversion Practice Example: Convert 12 gallons to units of quarts.
31 Unit Conversion Practice Example: Convert 4 ounces to kilograms.