A guitar string is set into vibration so that it produces a sound. The wave speed in the guitar string is always $440\ \text{m s}^{-1}$. The vibrating string also generates a sound wave that travels through the air at a speed of $330\ \text{m s}^{-1}$. Which graph shows how frequency $f$ changes with wavelength $\lambda$ for the waves in the string and in the air?
Physics 9702 · AS & A Level · Progressive waves