Simple Harmonic Motion bowlesphysics（简谐运动bowlesphysics）.pdfVIP

Simple Harmonic Motion AP Physics B Simple Harmonic Motion Back and forth motion that is caused by a force that is directly proportional to the displacement. The displacement centers around an equilibrium position. F α x s Springs – Hooke’s Law One of the simplest type of simple harmonic motion is called Hookes Law. This is primarily in reference to SPRINGS. The negative sign only F α x tells us that “F” is what is s called a RESTORING k = Constant of Proportionality FORCE, in that it works in k = Spring Constant(Unit : N/m) the OPPOSITE direction of the displacement. F = kx or − kx s Hooke’s Law Common formulas which are set equal to Hookes law are N.S.L. and weight Example A load of 50 N attached to a spring hanging vertically stretches the spring 5.0 cm. The spring is now placed horizontally on a table and stretched 11.0 cm. What force is required to stretch the spring this amount? F = kx Fs = kx s = k Fs = (10000)(.11 ) 50 (0.05 ) F = 110 N k = 1000 N/m s Hooke’s Law from a Graphical Point of View Suppose we had the following data: F = kx s x(m) Force(N) F k = s 0 0