The length of a tube in a wind instrument affects the wavelength of sound waves because only specific wavelengths resonate within the tube, determined by its length. Longer tubes can accommodate more compressions and rarefactions, but not all wavelengths can persist; only those that match the tube's dimensions are reinforced. The speed of sound remains constant, as it is a property of the gas inside the tube, regardless of the tube's length. Therefore, the relationship between tube length and wavelength is crucial for understanding sound production in wind instruments. This highlights the importance of standing waves in determining which wavelengths are amplified.