Equivalent mass of a coil spring Available to Purchase

The Hooke’s law force on a coil spring often constitutes a student’s first introduction to the properties of simple harmonic motion. The usual treatment assumes a vertical massless spring, held fixed at one end and stretched by a hanging mass M at the other. An occasional text, however, points out that the treatment, in the case of a hanging spring, can be improved by taking into account the equivalent mass $mo/3$ of the spring. It is only necessary to add$mo/3$ to the hanging mass M in the expression that relates the frequency of the spring oscillations to M and to the spring constant k.