 Problem solving involves developing a plan, and mapping out a pathway through a problem before solving.  Any two measurements that are equal to one another but expressed in different units can be written as a ratio.  A ratio of equivalent measurements is called a conversion factor and is equal to unity.  Conversion factors are used in the problem solving technique of dimensional analysis.  A ratio of equivalent measurements has two forms. The correct conversion factor for solving a particular problem will have the known unit in the denominator and the unknown unit in the numerator.  Conversion problems in which you are asked to express a measurement in some other unit are easily solved using dimensional analysis.  In dimensional analysis, units are used to help write the solution to a problem.  More than one conversion factor may be required in some more complex conversion problems.  The given measurement in a rate problem has a ratio of units. Rate problems may be solved by converting the unit in the numerator followed by converting the unit in the denominator.

Chapter Vocabulary Conversion factor: how measurements are related to each other. Dimensional anaylsis: using units to figure out problems unit Grams, ounces, and other labels which tell you what type of quantity you are using. density How mass is related to volume. Boling point The temperature at which the vapor pressure equals atmospheric pressure temperature A measure of the hotness or coldness of a substance

Dimensional Analysis Step 1: copy the known Step 2: identify and copy the conversion factor Step 3: multiply the numerator, divide the denominator

More vocabulary Celsius Metric measurement of temperature volume Length x width x height or area x height. How much space is occupied by an object. mass The quantity of matter known The thing given in the problem. Unknown The thing you are trying to find in the problem

5280 feet = 1 mile 16 oz = 1 pounds 12 inches = 1 foot 1 pint = 473 milliliters 1 ton = 2000 pounds 5 carats = 1 kilograms 32 miles = ? feet 32 miles _5280 feet_ 1 mile = feet = 170,000 feet 45 oz = ? pounds 45 oz _1 pound_ 16 oz = pound = 2.8 pound Step 1: copy the known Step 2: identify and copy the conversion factor Step 3: multiply the numerator, divide the denominator

3.4 pints = ? milliliters 5.6 pounds = ? tons 5280 feet = 1 mile 16 oz = 1 pounds 12 inches = 1 foot 1 pint = 473 milliliters 1 ton = 2000 pounds 5 carats = 1 kilograms 3.4 pints _473 mL_ 1 pint = mL = 1600 mL 5.6 pounds _1 ton_ 2000 pounds = tons