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Warm Up-September 7 th. Flower Power - PowerPoint PPT Presentation

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The Metric System

Warm Up-September 7th Flower PowerSpongeBob loves to garden and wants to grow lots of pink flowers for his pal Sandy. He bought a special Flower Power fertilizer to see if it will help plants produce more flowers. He plants two plants of the same size in separate containers with the same amount of potting soil. He places one plant in a sunny window and waters it every day with fertilized water. He places the other plant on a shelf in a closet and waters it with plain water every other day.

What did SpongeBob do wrong in this experiment? Explain.What should SpongeBob do to test the effectiveness of Flower Power fertilizer?Warm Up 8/21Stacy decided to do an experiment to test which brand of artificial sugar tasted the most like real sugar. In the experiment she tested three different brands Splenda, Equal and Stevia. Name the independent variable, dependent variable and at least 3 controls in Stacys experiment.The Metric SystemClass Notes

The Metric System IsThe standard system used around the world by scientists.We refer to it as the International System of Units or SI.It is based on a system of decimals.It is used to measure length, mass, volume, density and temperature.

Common Metric UnitsKilo = 1000Super SizedHecta = 100BiggerDeka = 10BigBase Unit Meter Liter GramDeci = 0.1SmallCenti = 0.01SmallerMilli = 0.001Smallest

Remember: King Henry Died By Drinking Chocolate Milk

Mass vs. WeightMassThe amount of matter in an objectTool: triple beam balanceUnit: gramConstant no matter where the object is locatedWeightThe amount of gravitational pull on an objectTool: spring scaleUnit: newtonVaries depending on locationMass and Weight: SimilaritiesAs the mass rises so does weightWe use both to describe the heaviness of an objectOn earth these go up and down togetherTheory vs. LawTheoryAn explanation for many hypothesis and observationsExplains an observation and helps predict what may happen in the futureMay change as new observations ariseLawA summary of many experimental resultsTells you how things workTells you what will happenLengthThe distance from one point on an object to anotherMeasured in MetersThe smallest unit of length is the millimeter (mm). When would you use millimeters to measure length?125 mm = ___ cmLargest unit of length is Kilometer, what would you measure using the km?

MassMeasured in gramsMass measures the amount of matter in an object (BUT NOT THE WEIGHT!)Measured using a triple beam balance

WeightThe measure of gravitational pull on an object.Measured in newton's using a spring scale.

VolumeMeasured in LitersVolume is the amount of space an object takes up1 mL = 1cm3

DensityThe amount of mass in a given volume.Density = mass/volumeg/mLWhich is more dense?

TemperatureMeasured in CelsiusWater freezes at 0C and boils at 100C

InertiaAn objects resistance to change in motionA change in motion could be moving something or slowing something downInertia is directly related to massthe more massive something is the harder it will be to change its motion.

Would it be easier toStop a football player or toddler running down the fieldMove a cargo ship or a sailboatLift a full dresser or empty it out and then lift itSlow down a single engine plane or a commercial airlinerIt is harder to stop or move things that have greater mass or more inertia!Warm Up 9/9Which SI unit would you probably use to express the height of your desk?

What would be the appropriate tool to use when measuring the mass of a spoon?

Ms. Gould is measuring small amounts of liquid chemicals out to be used in an experiment. Name the tool and SI unit that she is most likely using.Metric ConversionsSince the metric system is a decimal system, it is easy to convert between units.There are several methods to use:The stair step methodDecimal HoppingFactor Label MethodThe Stair Step Method

Kilo - k1000 unitsHecto - h100unitsDeka - da 10unitsBasic Unit (g, m, L)Deci - d0.1units

Centi - c0.01units Milli - m0.001unitsTo convert to a larger unit, move decimal point to the left or divide.

To convert to a smaller unit, move decimal point to the right or multiply.

1.) 1000 mg = 1 g3.) 109 g = ____ kg

2.) 160 cm = 1600 mm4.)14 km = ____ mDecimal HoppingOnce you master the stairs, decimal hopping should become easier. Since the metric system is set up by powers of ten all we have to do is move the decimal point to change units.If you are moving to a LARGER unit move the decimal to the LEFT.If you are moving to a SMALLER unit move the decimal to the RIGHT.

Example: smaller to largerMoving to a larger unit33 m = ____ km 1st place your decimal point33. m = ____ km 2nd, how many places away is km from m? Larger moves LEFT.33. m = ____ km

33. m = .033 km

Example: larger to smallerMoving to a smaller unit67.2 dm = ____ mm 1st the decimal is placed, we will start hopping from that point67.2 dm = ____ mm 2nd , how many places is dm from mm?67.2 dm = ____ mm

67.2 dm = 6720 mmTry Some460 L = ____ mL90 cg = ____ kg23.56 km = ____ hm

460 L = 460,000 mL90 cg = .0009 kg23.56 km = 235.6 hm

Another Method for ConversionFactor LabelSometimes it is not as easy as moving the decimal.For instance when converting from pounds to kilograms we cannot just move the decimalfor these conversion we use the factor label method.Step 1:Example: how many seconds are in 50 hours?

Put the known quantity in the upper-left space:50 hrStep 2:Put the conversion factor in the next set of boxes to the right. Make sure that units match diagonally:50 hr60 min____1 hrStep 3:Cross out, or cancel, the units that appear the same on both top and bottom:50 hr60 min____1 hrStep 4:Now ask, is the unit thats not crossed out the one that I want?If the answer is yes, then continue to step 5If the answer is no; return to step 2

50 hr60 min 60 sec____1 hr 1 minStep 5:To solve the problem, multiply the numbers on the top row.50 x 60 x 60 = 180,000Then multiply the numbers on the bottom row1 x 1 x 1

50 hr60 min 60 sec____1 hr 1 minStep 5 (cont.):Now, divide the top rows product by the bottom rows product180,000 / 1 = 180,000 secondsTicket Out the DoorUse the factor label method to determine how many inches are in 20 miles.12 in = 1 foot3 feet = 1 yard5, 280 feet = 1 mile