$$\require{cancel}$$

# 1: The Nature of Science and Physics

In this text, you will begin to explore the history of the formal study of physics, beginning with natural philosophy and the ancient Greeks, and leading up through a review of Sir Isaac Newton and the laws of physics that bear his name. You will also be introduced to the standards scientists use when they study physical quantities and the interrelated system of measurements most of the scientific community uses to communicate in a single mathematical language.

• 1.0: Prelude to Science and the Realm of Physics, Physical Quantities, and Units
In this text, you will begin to explore the history of the formal study of physics, beginning with natural philosophy and the ancient Greeks, and leading up through a review of Sir Isaac Newton and the laws of physics that bear his name. You will also be introduced to the standards scientists use when they study physical quantities and the interrelated system of measurements most of the scientific community uses to communicate in a single mathematical language.
• 1.1: Physics: An Introduction
Science seeks to discover and describe the underlying order and simplicity in nature. Physics is the most basic of the sciences, concerning itself with energy, matter, space and time, and their interactions. Scientific laws and theories express the general truths of nature and the body of knowledge they encompass. These laws of nature are rules that all natural processes appear to follow.
• 1.2: Physical Quantities and Units
Physical quantities are a characteristic or property of an object that can be measured or calculated from other measurements. Units are standards for expressing and comparing the measurement of physical quantities. All units can be expressed as combinations of four fundamental units. The four fundamental units we will use in this text are the meter (for length), the kilogram (for mass), the second (for time), and the ampere (for electric current). These units are part of the metric system, which
• 1.3: Accuracy, Precision, and Significant Figures
Science is based on observation and experiment—that is, on measurements. Accuracy is how close a measurement is to the correct value for that measurement. The precision of a measurement system is refers to how close the agreement is between repeated measurements (which are repeated under the same conditions).
• 1.4: Approximation
As you develop problem-solving skills, you will also develop skills at approximating. You will develop these skills through thinking more quantitatively, and by being willing to take risks. As with any endeavor, experience helps, as well as familiarity with units. These approximations allow us to rule out certain scenarios or unrealistic numbers. Approximations also allow us to challenge others and guide us in our approaches to our scientific world.
• 1.E: The Nature of Science and Physics (Exercises)

Thumbnail: This parabola-shaped lava flow illustrates the application of mathematics in physics—in this case, Galileo's law of falling bodies. Image used with permission (Jim D. Griggs, HVO (USGS) staff photographer @ http://pubs.usgs.gov/dds/dds-80).

### Contributors

• Paul Peter Urone (Professor Emeritus at California State University, Sacramento) and Roger Hinrichs (State University of New York, College at Oswego) with Contributing Authors: Kim Dirks (University of Auckland) and Manjula Sharma (University of Sydney). This work is licensed by OpenStax University Physics under a Creative Commons Attribution License (by 4.0).