Halliday, Resnick & Walker — Waves–I: Problem Problem_27

A sinusoidal wave is sent along a string with a linear density of \(2.0 \text{ g/m}\). As it travels, the kinetic energies of the mass elements along the string vary. Figure 16.14a gives the rate \(dK/dt\) at which kinetic energy passes through the string elements at a particular instant, plotted as a function of distance \(x\) along the string. Figure 16.14b is similar except that it gives the rate at which kinetic energy passes through a particular mass element (at a particular location), plotted as a function of time \(t\). For both figures, the scale on the vertical (rate) axis is set by \(R_s = 10 \text{ W}\). What is the amplitude of the wave?