2 SI Units are... International Standards Abbreviated SI from the French Le Systeme Internationale d’Unites
3 What is a standard? It is an exact quantity that people agree to use for comparison. Why are measurement standards important? A meter in the U.S. is the same as a meter in France, or China, or any other country in the world. This allows us to share data.
5 centi- meter milli- liter kilo- gram (0.01) (.001) (1000) Putting It All Together… hundredth of a meter thousandth of a liter thousand grams
6 SI Units for Measurement Used in Science Length Volume Mass Temperature Measured in meters (m) Measured in Liters (L) Measured in grams (g) Measured in degrees Celsius ( O C) Metric ruler Graduated cylinder Balance Thermometer Type Base Unit Tool Time Measured in seconds (s) Clock L x W x H
8 Let’s Practice……. 36 cm = ___ m 28 mL = ____ L 5.25 m = _____ mm 480 mg = ____ g
9 When measuring an object with a ruler, never start with at the “0” mark. wear and tear Rulers are less accurate due to wear and tear at the ends. Begin at the 2, 4, 5 or 6 cm mark in order to get the most accurate mark. Using a Ruler 1.2 cm The red line would be 1.2 cm because the “5” is the starting point. What is the length of the red line? 6.2 cm or 1.2 cm 5 6
10 Reading the Meniscus When measuring liquid volume in a graduated cylinder, a meniscus often forms where the liquid ends. graduated cylinders In order to read this liquid volume, you must be at “eye- level” to the level of the liquid. BOTTOM You take the reading at the BOTTOM of the meniscus. The liquid level is 36.5 mL.
11 Read these liquid volumes in mL: 11.5 mL 76.0 mL A. B.