ABSTRACT
Consider a compact mass m that slides over a frictionless horizontal surface. Suppose that the mass is attached to one end of a light horizontal spring whose other end is anchored in an immovable wall. (See Figure 1.1.) At time t, let x(t) be the extension of the spring, that is, the difference between the spring’s actual length and its unstretched length. x(t) can also be used as a coordinate to determine the instantaneous horizontal displacement of the mass.
