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Apuntes

• Subtopic: Understanding Motion Motion happens all around us. Every day, we see objects such as cars, people, and soccer balls move in different directions with different speeds. We are familiar with the idea of motion, but it requires a special effort to analyze motion as a physicist does. One-dimensional motion is the simplest form of motion. One way to simplify the concept of motion is to consider only the kinds of motion that take place in one direction. An example of this one-dimensional motion is the motion of a commuter train on a straight track, as in Figure 1. In this one-dimensional motion, the train can move either forward or backward along the tracks. It cannot move left and right or up and down. This chapter deals only with one-dimensional motion. In later chapters, you will learn how to describe more complicated motions such as the motion of thrown baseballs and other projectiles. • Subtopic: Frame of Reference Motion takes place over time and depends upon the frame of reference. It seems simple to describe the motion of the train. As the train in Figure 1 begins its route, it is at the first station. Later, it will be at another station farther down the tracks. ...