Physics for Technology, Second Edition

Daniel H. Nichols

• Publisher: CRC Press
• Year: 2018
• eBook ISBN: 9781351207256
• Topic: Physical Sciences
• Subtopic: Physics
• Index: Physics

This text provides an introduction to the important physics underpinning current technologies, highlighting key concepts in areas that include linear and rotational motion, energy, work, power, heat, temperature, fluids, waves, and magnetism. This revision reflects the latest technology advances, from smart phones to the Internet of Things, and all kinds of sensors. The author also provides more modern worked examples with useful appendices and laboratories for hands-on practice. There are also two brand new chapters covering sensors as well as electric fields and electromagnetic radiation as applied to current technologies.

1

Units and Measurements

Units are based on standards wherein we define measurable quantities, such as length, mass, time, and so on. The units vary depending on the size of things we are measuring. For example, we would not measure the distance across the United States in inches; that is much too small a unit. Instead we would use a unit such as miles or kilometers. It is very handy to be able to convert back and forth between like units, such as miles, inches, and kilometers. This chapter will present some of the various ways of measuring, recording, and converting between units (Figure 1.1).

FIGURE 1.1 Measuring instruments.

1.1 SCIENTIFIC NOTATION

Many measurements are written in scientific notation, which is a method of writing big and small numbers in a compact way. In this notation, all numbers are written in a power of ten.

10=1.0×101100=1.0×1021,000=1.0×103

The number above the ten is called an exponent, which tells how many zeros come after the one.

For numbers such as 1/10 or 1/100, we use a minus sign in the exponent.

110=1.0×10−11100=1.0×10−211,000=1.0×10−3

The number in the exponent now tells how many zeros follow the one at the bottom of the fraction.

Numbers such as 638,000 or 0.00012 can be written in scientific notation.

638,000=6.38×105←Decimalmovedtotheleftfiveplaces0.00012=1.2×10–4←Decimalmovedtotherightfourplaces

Place the decimal after the first nonzero digit on the left and count the number of places the decimal was moved over. Use that number in the exponent. If the decimal is moved to the left, the exponent is positive. If the decimal is moved to the right, the exponent is negative.

1.2 UNITS OF LENGTH

In the English system, length units are miles, yards, feet, and inches. Another system is the SI system. SI stands for the Système International (International System, in English). The metric system is part of the SI system. The basic unit of length in SI is meter. All units of length are based on it.

In the early part of the twentieth century, the standard of measuring length was defined using a metal bar that was kept in a vault in France. To calibrate a meter stick, one would have to travel to France and compare the two. This was very inconvenient! It therefore became necessary to devise a generic method of measuring length so that the whol...

Table of contents

• Cover
• Half Title
• Series Page
• Title Page
• Copyright Page
• Dedication Page
• Table of Contents
• Preface
• Acknowledgements
• Author
• Chapter 1 Units and Measurements
• Chapter 2 Linear Motion
• Chapter 3 Force and Momentum
• Chapter 4 Energy, Work, and Power
• Chapter 5 Rotational Motion
• Chapter 6 Machines
• Chapter 7 Strength of Materials
• Chapter 8 Fluids
• Chapter 9 Fluid Flow
• Chapter 10 Temperature and Heat
• Chapter 11 Thermodynamics: Heat Engines, Heat Pumps, and Thermal Expansion
• Chapter 12 Electric Force
• Chapter 13 Electricity
• Chapter 14 Magnetism
• Chapter 15 Waves
• Chapter 16 Light
• Chapter 17 Data Acquisition-Sensors and Microcontrollers
• Chapter 18 Smartphones and Physics
• Appendix A: Trigonometry Review
• Appendix B: Supplementary Lab Experiments
• Appendix C: Unit Conversions
• Appendix D: Answers to Odd Numbered Back of the Chapter Problems
• Index