Measuring Using the Metric System!

Three ways to use the metric system Length Volume Mass

Units for Length, Volume, and Mass Length-Meter (m) Mass-Gram (g) Volume-Liter (L)

Length

The measurement of a distance from one point to another. Length The measurement of a distance from one point to another.

Use a ruler or meter stick Ways to Measure Length Use a ruler or meter stick

English vs. Metric Units Which is longer? A. 1 mile or 1 kilometer B. 1 yard or 1 meter C. 1 inch or 1 centimeter 1.6 kilometers 1 mile 1 yard = 0.9444 meters 1 inch = 2.54 centimeters Left Image: http://webapps.lsa.umich.edu/physics/demolab/controls/imagedemosm.aspx?picid=1167 Right Image: http://share.lancealan.com/N800%20ruler.jpg

SI unit for Length Kilometer (km)-compares to a mile Meter (m)- compares to a yard Centimeter (cm)- compares to an inch Millimeter (mm)- for really tiny distances PRACTICE: Which unit would you use to measure a length of a thumb tack?

Special Note!!! Whenever you see a “m” by itself, it will stand for meter, and not milli.

Measuring Length How many millimeters are in 1 centimeter? 1 centimeter = 10 millimeters How many millimeters are in 1 centimeter? What is the length of the line in centimeters? _______cm What is the length of the line in millimeters? _______mm What is the length of the line to the nearest centimeter? ________cm HINT: Round to the nearest centimeter – no decimals. Ruler: http://www.k12math.com/math-concepts/measurement/ruler-cm.jpg

Mass

Mass A measure of the amount of matter in an object.

3 Types of Matter 1.) Solid-matter that has definite shape and definite volume 2.) Liquid-matter that has definite volume, but not definite shape 3.) Gas-matter that has no definite shape or volume

Ways to measure mass Use a balance or an electronic scale

English vs. Metric Units 1 pound = 453.6 grams Which is larger? 1. 1 Pound or 100 Grams 2. 1 Kilogram or 1 Pound 3. 1 Ounce or 1000 Milligrams 100 kilogram = 220 pounds 1 ounce of gold = 28,349.5 milligrams

SI unit for mass Kilogram (kg)-compared to a pound Gram (g)-compared to an ounce Practice: Which unit would you use to measure a pill?

_______ + ______ + _______ = ________ g Measuring Mass We will be using triple-beam balances to find the mass of various objects. The objects are placed on the scale and then you move the weights on the beams until you get the lines on the right-side of the scale to match up. Once you have balanced the scale, you add up the amounts on each beam to find the total mass. What would be the mass of the object measured in the picture? _______ + ______ + _______ = ________ g Top Image: http://www.southwestscales.com/Ohaus_Triple_Beam_750-SO.jpg Bottom Image: http://www.regentsprep.org/Regents/biology/units/laboratory/graphics/triplebeambalance.jpg

Measuring Mass – Triple-Beam Balance 1st – Place the film canister on the scale. 2nd – Slide the large weight to the right until the arm drops below the line. Move the rider back one groove. Make sure it “locks” into place. 3rd – Repeat this process with the top weight. When the arm moves below the line, back it up one groove. 4th – Slide the small weight on the front beam until the lines match up. 5th – Add the amounts on each beam to find the total mass to the nearest tenth of a gram.

Mass vs. Weight Mass and weight get confused. Weight is the downward force exerted by an object due to gravity. Mass is the amount of matter in an object. (If you were in outer space, you would weigh less, but still have the same mass as you would on Earth)

Volume Solid vs. Liquid

The amount of space an object takes up (physical property) Volume The amount of space an object takes up (physical property)

Tools used to measure volume Beaker Florence Flask Erlenmeyer Flask Graduated Cylinder

English vs. Metric Units Which is larger? A. 1 liter or 1 gallon B. 1 liter or 1 quart C. 1 milliliter or 1 fluid ounce 1 fl oz = 29.573 ml 1 12-oz can of soda would equal approximately 355 ml. 1 gallon = 3.79 liters It would take approximately 3 ¾ 1-liter bottles to equal a gallon. 1 quart = 0.946 liters

SI ( System International) Unit for volume Solid-Cubic Meter (m³) cm³ is more commonly used Liquid- Liter (L)-compared to gallons Milliliter (mL)- compared to fluid ounces Using Liquid Displacement 1mL = 1 cmᵌ

Ways to measure solid volume 1.) Formula : Volume = Length x Width x Height 2.) Liquid Displacement- (For or an object that cannot be measured by length, width, and height.) Put a measurable amount of water into a graduated cylinder, record the amount of water, place the object in the cylinder, record where the new amount of water is, subtract the second measurement from the first measurement=Volume!)

Measuring Solid Volume 10 cm 9 cm 8 cm We can measure the volume of regular object using the formula length x width x height. _____ X _____ X _____ = _____ http://resources.edb.gov.hk/~s1sci/R_S1Science/sp/en/syllabus/unit14/new/testingmain1.htm We can measure the volume of irregular object using water displacement. Amount of H2O with object = ______ About of H2O without object = ______ Difference = Volume = ______ Click here for an online activity about volume. Choose Lessons  Volume & Displacement

Reading a graduated cylinder Graduated Cylinders come in all shapes and sizes and are measured in ml. Water molecules attract to the glass causes the water surface to curve, therefore to measure accurately, one must look at the meniscus at eye level. Therefore, when measuring, measure at the bottom of the meniscus or curve.

Measuring Liquid Volume What is the volume of water in each cylinder? Images created at http://www.standards.dfes.gov.uk/primaryframework/downloads/SWF/measuring_cylinder.swf A B C