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3.3 Conversion Factors Conversion Factors What happens when a measurement is multiplied by a conversion factor? 3.3 Conversion Factors A conversion factor is a ratio of equivalent measurements. The ratios 100 cm/1 m and 1 m/100 cm are examples of conversion factors. 3.3 Conversion Factors When a measurement is multiplied by a conversion factor, the numerical value is generally changed, but the actual size of the quantity measured remains the same. 3.3 Conversion Factors The scale of the micrograph is in nanometers. Using the relationship 109 nm = 1 m, you can write the following conversion factors. 3.3 Dimensional Analysis Dimensional Analysis Why is dimensional analysis useful? 3.3 Dimensional Analysis Dimensional analysis is a way to analyze and solve problems using the units, or dimensions, of the measurements. 3.5 3.5 for Sample Problem 3.5 3.6 3.6 3.6 for Sample Problem 3.6 For Sample Problem 3.6 3.3 Converting Between Units Converting Between Units What types of problems are easily solved by using dimensional analysis? 3.3 Converting Between Units Problems in which a measurement with one unit is converted to an equivalent measurement with another unit are easily solved using dimensional analysis. 3.7 3.7 3.7 for Sample Problem 3.7 3.3 Converting Between Units Multistep Problems When converting between units, it is often necessary to use more than one conversion factor. 3.8 3.8 3.8 for Sample Problem 3.8 3.3 Converting Between Units Converting Complex Units Many common measurements are expressed as a ratio of two units. If you use dimensional analysis, converting these complex units is just as easy as converting single units. It will just take multiple steps to arrive at an answer. 3.9 3.9 3.9 for Sample Problem 3.9 3.3 Section Quiz 1. 1 Mg = 1000 kg. Which of the following would be a correct conversion factor for this relationship? a. 1000. b. 1/1000. c. ÷ 1000. d. 1000 kg/1Mg. 3.3 Section Quiz 2. The conversion factor used to convert joules to calories changes a. the quantity of energy measured but not the numerical value of the measurement. b. neither the numerical value of the measurement nor the quantity of energy measured. c. the numerical value of the measurement but not the quantity of energy measured. d. both the numerical value of the measurement and the quantity of energy measured. 3.3 Section Quiz 3. How many g are in 0.0134 g? a. 1.34 10–4 b. 1.34 10–6 c. 1.34 106 d. 1.34 104 3.3 Section Quiz 4. Express the density 5.6 g/cm3 in kg/m3. a. 5.6 106kg/m3 b. 5.6 103kg/m3 c. 0.56 kg/m3 d. 0.0056 kg/m3 Slide 33 of 43 © Copyright Pearson Prentice Hall END OF SHOW