In this paper we consider the question of the energy content and energy transfer in string waves, point out why
the description of the potential energy in terms of the slope of the string fails for standing waves, and how to treat
the potential energy in a way that is applicable to both traveling and standing waves. We assume throughout that
the string has zero potential energy at equilibrium, that the string is frictionless, and that no energy is supplied to
drive the waves. We further assume that the tension τ is uniform along the string, which is equivalent to idealizing
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the string as having vanishing Young’s modulus, so that no nonlinear effects excite longitudinal modes in the string.
This paper is particularly relevant to physics and engineering majors who take the introductory physics with calculus
course, and to instructors of such courses