Metric Units. The Metric system is so simple! It is based on the number 10!

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1 Metric Units Name The Metric system is so simple! It is based on the number 10! Below is a diagram of a section of a ruler Each numbered line represents one centimeter Each small line represents one tenth of a ruler (e.g. point A) The larger mark between numbered lines represents one five tenths of a centimeter (e.g. point G) In the metric system fractions are not used, only decimals. Determine the length indicated by each point on the ruler. include the unit (cm). A B C D E F G The metric system uses base units for: Length Meter, Mass Gram Volume Liter and prefixes to indicate size. From largest to smallest they are Kilo, Hecta, Deca, (BASE UNIT), Deci, Centi, Milli We can use the following mnemonic to remember these in order Ki ng H enry D oesn t U sually D rink C hocolate M ilk

2 It is also easy to convert between units by moving the decimal point according to the following diagram. The following abbreviations are used for each prefix Length: km= kilometers, hm= hectometer, dam= dekameter, m= meter, dm= decimeter, cm= centimeter, mm= millimeter In science it is important to be as accurate and precise as possible.

3 Let s start measuring! LENGTH How much does each one equal. a. 1m= cm b. 1cm= mm c. 1km= m Which measurement is the largest. a. 14mm or 1 cm b. 145 m or 145 km c. 334 m or 1 km d. 3.4 cm or 30 mm e. 1m or 990 cm f. 10 km or 100 cm Use a metric ruler or meter stick to find each measurement. (remember units) length of the line in centimeters Height of the rectangle in millimeters Length of the rectangle in millimeters Radius of the circle to the nearest millimeter Diameter of the circle in centimeters Diameter of the circle to the nearest centimeter

4 Volume of the box in cubic centimeters= x x = (Measure to the nearest centimeter before multiplying.) Find the length of an unsharpened pencil (including eraser) in millimeters. What is your height in centimeters? What is your height in meters? Use your shoe and a metric ruler to complete this section. Keep your shoes on for this one! (remember units) (a) What is the length of your shoe to the nearest centimeter? (b) How many shoes would it take (heel to toe) to make 1 meter? (c) How many shoes would it take to make 1 kilometer? Use ten pennies and a metric ruler to complete this section. a) How tall is a stack of ten pennies in centimeters? (b) How tall would a stack of 100 pennies be in centimeters? (c) How tall would a stack of 1000 pennies be in centimeters? Circle the BEST metric unit for each. (a) The length of an eyelash mm cm m km (b) The height of a flagpole mm cm m km (c) The length of a strand of spaghetti mm cm m km (d) The distance from Chicago, IL, to Peoria, IL. mm cm m km Measuring Volume Remember the base unit for volume is a Liter We will be using graduated cylinders which measure by Milliliter (ml)

5 Part A : Count your drops! Take a guess How many drops of water will it take to equal 1 milliliter? drops Follow the directions to find the number of drops in 1 milliliter of water, then answer the questions. You will need a small graduated cylinder (25 ml), a beaker of water, and an eyedropper for this section. (1) Fill a small graduated cylinder with 10 ml of water. (2) Count the number of drops it takes to raise the water to 11 ml. Record the number in the chart. (3) Leave the water in the graduated cylinder and count the number of drops it takes to raise the water to 12 ml. Record the number in the chart. (4) Leave the water in the graduated cylinder and count the number of drops it takes to raise the water to 13 ml. Record the number in the chart. (5) Calculate your average and round to the nearest tenth. # drops to 11 ml # drops to 12 ml # drops to 13 ml Average Based on your average, how close were you to your guess? Based on your average, how many drops would it take to make 1 liter? Part B : Water Displacement Follow the directions to find the volume of three marbles using water displacement. (1) Add 20 ml of water to a 100 ml graduated cylinder. Record this amount in the chart. (2) Add three marbles to the cylinder and measure the volume. Record this amount in the chart. (3) Find the difference between the two measurements and record in the chart. The difference between the two measurements will be the volume of the three marbles. Volume of water before adding marbles Volume of water after adding marbles Difference in volume Volume of three marbles (remember units) Part C: Volume by Formula Use the formula to find the volume of the box. Measure to the nearest centimeter (no decimals) before calculating your answer. Volume= Length x Width x Height x x = cm 3 Adapted from T. Trimpe