Higher order harmonics on a string exhibit lower amplitudes compared to the fundamental frequency due to energy dissipation and geometric factors. As tension increases, the amplitude of standing waves decreases, with lower tension allowing for larger amplitudes across all modes. The relationship between frequency and energy indicates that higher frequencies dissipate energy more quickly, leading to reduced amplitudes for higher harmonics when the same excitation energy is applied. The fundamental theorem of Fourier series explains that as frequency increases, the coefficients for higher harmonics approach zero, resulting in lower amplitudes. Overall, the amplitude of standing waves is influenced by the tension of the string and the geometry of the waveforms.