Page 24 - Appplied Mathematics for the Petroleum and Other Industries, 5th Edition

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5

Some Physical Quantities and

Their Measurement

OBJECTIVES
Upon completion of chapter 5, the student will be able to—

1. Describe the difference between fundamental quantities and derived
quantities.
2. Convert measurements from U.S. conventional units to SI metric units
and from SI metric units to conventional units.
3. Convert units of measurement to equivalent units in order to solve problems.
4. Use and read proper symbols and abbreviations for common measurement
units.
5. Measure distance using a ruler or scale.
6. Solve problems using length, area, and volume measurements.
7. Convert temperatures from one scale of measurement to another.
Petroleum Extension-The

9. Solve problems involving measurements of weight, mass, force, work, power,
pressure, density, and specific gravity.
10. Read simple electrical circuits and solve problems involving voltage, cur-
rent, and resistance.
11. Solve for kilowatt-hours and other electrical power measurements.

INTRODUCTION

Quantity has many definitions. As used here, a physical quantity is something that
has dimensions and can be measured, such as length, mass (weight), and time.
These three physical quantities are fundamental quantities. A fundamental quan-
tity cannot normally be divided into other quantities. Seven major fundamental
quantities exist: (1) length, (2) mass, (3) time, (4) electricity, (5) luminous intensity,
(6) temperature, and (7) the amount of a substance.
Another term for a fundamental quantity is dimension. Dimensions include
distance (length), time, and mass (weight). So, we can say, for example, that the
dimension of a room is 12 feet wide by 14 feet long by 8 feet high. We can also say
8. Work in all increments of time measurement.University of Texas at Austin
that it takes two hours to complete a journey, and that a car weighs 3,250 pounds.
Scientists derived several nonfundamental quantities from the seven
fundamental quantities. Consequently, they called nonfundamental quantities
derived quantities. For example, velocity is a derived physical quantity because
it is composed of distance (length) and time. So, when we speak of velocity, we
speak of it in terms of miles per hour, feet per second, and so forth. Another
example of a derived quantity is pressure. It is a measure of a force on a given
area—for example, pounds per square inch.
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