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Measuring in the Science Laboratory. T. Trimpe 2008 http://sciencespot.net/. Measuring Length. Length- is measured with a ruler or a meter stick. Common units for length are meters, centimeters, millimeters . How many millimeters are in 1 centimeter?. 1 cm = 10 mm.
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Measuring in the Science Laboratory T. Trimpe 2008 http://sciencespot.net/
Measuring Length Length- is measured with a ruler or a meter stick. • Common units for length are meters, centimeters, millimeters. How many millimeters are in 1 centimeter? 1 cm = 10mm Ruler: http://www.k12math.com/math-concepts/measurement/ruler-cm.jpg
Measuring Volume Volume is the amount of space an object takes up. There are 3 different ways to measure volume: A. Volume of a liquid B. Volume of a regular solid C. Volume of an irregular solid A B C
A. Measuring Volume of a Liquid We will be using a graduated cylinder to measure the volume of liquid. • First, place the graduated cylinder on a level surface. The surface of the liquid will form a curve called the meniscus. • The volume is read from the bottom of the • meniscus. • When using a graduated cylinder, make sure you are at eye-level with the level of the water. • The units used when measuring with a • graduated cylinder are called milliliters. Top Image: http://www.tea.state.tx.us/student.assessment/resources/online/2006/grade8/science/images/20graphicaa.gifBottom Image: http://morrisonlabs.com/meniscus.htm
9 cm 8 cm 10 cm B. Measuring Volume of a Regular Solid We can measure the volume of regular object using the formula length x width x height. • The units when measuring a regular solid are cm3. 10 cm 9 cm 720 cm3 8 cm _____ X _____ X _____ = _____
http://resources.edb.gov.hk/~s1sci/R_S1Science/sp/en/syllabus/unit14/new/testingmain1.htmhttp://resources.edb.gov.hk/~s1sci/R_S1Science/sp/en/syllabus/unit14/new/testingmain1.htm Amount of H2O with object = ______About of H2O without object = ______Difference = Volume = ______ C. Measuring Volume of an Irregular Solid We can measure the volume of irregular object using water displacement. • When an object is submerged in water, the water level will rise. The amount the water level rises is equal to the volume of the object. • This is called displacement. • The units when measuring an irregular solid are millimeters. 69 ml 65 ml 4 ml • Why is this method accurate? 1 ml = 1 cm3
Temperature • Temperature is measured with a thermometer. • Do not shake the thermometer down before using. • Measure temperature by leaving the bulb of the thermometer below the surface of a liquid. • Do not let thermometer touch bottom or sides of container. (See diagram in notes) • Read the thermometer at eye level. Watch column in the thermometer unit it stops moving. • Units for temperature are degrees Celsius (0C)
1 fl oz = 29.573 ml 1 12-oz can of soda would equal approximately 355 ml. 1 quart = 0.946 liters 1 gallon = 3.79 liters It would take approximately 3 ¾ 1-liter bottles to equal a gallon. 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
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 Pay attention to the scales for each cylinder.
kL Metric Units cL mL L Volume is the amount of space an object takes up. The base unit of volume in the metric system in the liter and is represented by L or l. Standard: 1 liter is equal to one cubic decimeter Metric Units 1 liter (L) = 1000 milliliters (mL) 1 milliliter (mL) = 1 cm3 (or cc) = 1 gram* Which is larger? Click the image to watch a short video about volume. A. 1 liter or 1500 milliliters B. 200 milliliters or 1.2 liters C. 12 cm3 or 1.2 milliliters* * When referring to waterLiter Image: http://www.dmturner.org/Teacher/Pictures/liter.gif