• Course Introduction

        • Time: 38 hours
        • Free Certificate
        In general, the goal of physics is to develop descriptions of the natural world that correspond closely to actual observations. Given this definition, the story behind everything in the universe, from rocks falling to stars shining, is one of physics. In principle, the events of the natural world represent no more than the interactions of the elementary particles that the material universe is made of. In practice, however, it turns out to be more complicated than that.

        As the system under study becomes more and more complex, it becomes less and less clear how the basic laws of physics account for the observations. Other branches of science, such as chemistry or biology, are needed. In principle, biology is based on the laws of chemistry, and chemistry is based on the laws of physics, but our ability to understand something as complex as life in terms of the laws of physics is well beyond our present knowledge. Physics is, however, the first rung on the ladder of our understanding of the physical universe.

        In this course, we will study physics from the ground up, learning the basic principles of physical laws, their application to the behavior of objects, and the use of the scientific method in driving advances in this knowledge. This first of two courses (the subsequent course is Introduction to Electromagnetism) will cover the area of physics known as classical mechanics. Classical mechanics is the study of motion based on the physics of Galileo Galilei and Isaac Newton. While mathematics is the language of physics, you will only need to be familiar with high school level algebra, geometry, and trigonometry. The small amount of additional math and calculus that we need will be developed during the course.

        First, read the course syllabus. Then, enroll in the course by clicking "Enroll me in this course". Click Unit 1 to read its introduction and learning outcomes. You will then see the learning materials and instructions on how to use them.

      • Unit 1: Introduction to Physics

        Our first step in this course is to gain a basic understanding of the language and analytical techniques that are specific to physics. This unit will include a brief outline of physics and the scientific method, measurement units and scientific notation, and the concepts of significant figures, order-of-magnitude estimates, and scaling.

        Completing this unit should take you approximately 6 hours.

      • Unit 2: Motion in a Straight Line

        Our formal study of physics begins with kinematics, which is defined as the study of motion without considering its causes. The word "kinematics” comes from a Greek term meaning "motion.” In this unit, we will study motion without worrying about what forces cause or change it. Such considerations come in later units. In this unit, we will examine the simplest type of motion - namely, motion along a straight line, or one-dimensional motion.

        Completing this unit should take you approximately 13 hours.

      • Unit 3: Kinematics in Two Dimensions

        Most motions in nature follow curved paths rather than straight lines. Motion along a curved path on a flat surface or a plane is two-dimensional and thus described by two-dimensional kinematics. Two-dimensional kinematics is a simple extension of the one-dimensional kinematics covered in the previous unit. This simple extension will allow us to apply physics to many more situations, and it will also yield unexpected insights about nature.

        Completing this unit should take you approximately 16 hours.

      • Unit 4: Dynamics

        The study of motion is kinematics, which describes the way objects move, their velocity, and their acceleration. Dynamics consider the forces that affect the motion of moving objects. Newton's laws of motion are the foundation of dynamics. These laws provide examples of the breadth and simplicity of principles under which nature functions. They are also universal laws in that they apply to similar situations on Earth as well as in space.

        Completing this unit should take you approximately 26 hours.

      • Unit 5: Circular Motion and Gravity

        In this unit, we will study the simplest form of curved motion: uniform circular motion, or motion in a circular path at constant speed. In some ways, this unit is a continuation of the previous unit on dynamics, but we will introduce new concepts such as angular velocity and acceleration, centripetal force, and the force of gravity.

        Completing this unit should take you approximately 15 hours.

      • Unit 6: Work and Energy

        Energy is the capacity of a physical system to perform work. It plays an essential role both in everyday events and in scientific phenomena. You can probably name many forms of energy from that provided by our foods to the energy we use to run our cars to the sunlight that warms us on the beach. Not only does energy have many interesting forms, but it is involved in almost all phenomena and is one of the most important concepts of physics.

        Energy can change forms, but it cannot appear from nothing or disappear without a trace. Thus, energy is one of a handful of physical quantities that we say is conserved.

        Completing this unit should take you approximately 14 hours.

      • Unit 7: Momentum and Collisions

        We use the term momentum in various ways in everyday language. We speak of sports teams gaining and maintaining the momentum to win. Generally, momentum implies a tendency to continue on course - to move in the same direction - and is associated with mass and velocity. Momentum has its most important application in analyzing collision problems, and, like energy, is important because it is conserved. Only a few physical quantities are conserved in nature, and studying them yields fundamental insight into how nature works, as we shall see in our study of momentum.

        Completing this unit should take you approximately 12 hours.

      • Unit 8: Statics and Torque

        What might desks, bridges, buildings, trees, and mountains have in common - at least in the eyes of a physicist? The answer is that they are ordinarily motionless relative to the Earth. Thus, their acceleration in the Earth frame of reference is zero. Newton's second law states that net F = ma,so the net external force is zero on all stationary objects and for all objects moving at constant velocity. There are forces acting, but they are balanced. That is, the forces are in equilibrium.

        Completing this unit should take you approximately 8 hours.

      • Unit 9: Angular Momentum

        Why do tornadoes spin so rapidly? The answer is that the air masses that produce tornadoes are themselves rotating, and when the radii of the air masses decrease, their rate of rotation increases. An ice skater increases her spin in an exactly analogous way. The skater starts her rotation with outstretched limbs and increases her spin by pulling them in toward her body. The same physics describes the spin of a skater and the wrenching force of a tornado. Clearly, force, energy, and power are associated with rotational motion. These and other aspects of rotational motion are covered in this unit. We will see that all important aspects of rotational motion either have already been defined for linear motion or have exact analogs in linear motion.

        Completing this unit should take you approximately 16 hours.

      • Study Guide

        These study guides will help you get ready for the final exam. They discuss the key topics in each unit, walk through the learning outcomes, and list important vocabulary terms. They are not meant to replace the course materials!

      • Course Feedback Survey

        Please take a few minutes to give us feedback about this course. We appreciate your feedback, whether you completed the whole course or even just a few resources. Your feedback will help us make our courses better, and we use your feedback each time we make updates to our courses.

        If you come across any urgent problems, email contact@saylor.org or post in our discussion forum.

      • Certificate Final Exam

        Take this exam if you want to earn a free Course Completion Certificate.

        To receive a free Course Completion Certificate, you will need to earn a grade of 70% or higher on this final exam. Your grade for the exam will be calculated as soon as you complete it. If you do not pass the exam on your first try, you can take it again as many times as you want, with a 7-day waiting period between each attempt.

        Once you pass this final exam, you will be awarded a free Course Completion Certificate.

      • Saylor Direct Credit

        Take this exam if you want to earn college credit for this course. This course is eligible for college credit through Saylor Academy's Saylor Direct Credit Program.

        The Saylor Direct Credit Final Exam requires a proctoring fee of $5. To pass this course and earn a Proctor-Verified Course Certificate and official transcript, you will need to earn a grade of 70% or higher on the Saylor Direct Credit Final Exam. Your grade for this exam will be calculated as soon as you complete it. If you do not pass the exam on your first try, you can take it again a maximum of 3 times, with a 14-day waiting period between each attempt.

        We are partnering with SmarterProctoring to help make the proctoring fee more affordable. We will be recording you, your screen, and the audio in your room during the exam. This is an automated proctoring service, but no decisions are automated; recordings are only viewed by our staff with the purpose of making sure it is you taking the exam and verifying any questions about exam integrity. We understand that there are challenges with learning at home - we won't invalidate your exam just because your child ran into the room!


        1. Desktop Computer
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        3. Webcam + Microphone
        4. 1mbps+ Internet Connection

        Once you pass this final exam, you will be awarded a Credit-Recommended Course Completion Certificate and can request an official transcript.