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MeasurementAspects of MeasurementsThere are four important aspects of measurement that we will deal with in this section. First is the property of the material or sample that you are measuring. For example, are you measuring how much space it takes up (volume) or how heavy it is (weight). Units, such as liters and pounds, are used to denote the property being measured. The second aspect of measurement is size. How big is the value that you are measuring? That is usually dealt with in two parts: how big the number is and what units were used. You need to show the units used in making the measurement. If all you know is that something weighs 13, you really don't know very much. Is it 13 grams, 13 milligrams, 13 pounds, or what? Third, you want the value that you measure to be accurate. If you are weighing something that has a mass between 4 and 5 grams, you want your value to be four-point-something grams, not seven-point-something grams. Accuracy involves using the proper measuring device and using it correctly. Fourth, you need to show how precise the measurement is. For example, did you measure to the nearest tenth, hundredth, or thousandth of a gram? One way to indicate precision is with significant digits. We will focus on significant digits in a later portion of this lesson. In summary, when you make measurements, you need accuracy, precision, size (including units), and property (also included in units). You will be expected to use accuracy, precision, and units in each measurement that you make. The pages in this section deal first with the properties we measure and then with the issues and skills associated with actually making measurements.
E-mail instructor: Eden Francis Clackamas Community College
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