i) A wave source moves away from you at 11.0 m/s, and the wavelength you compute is around 22% more than what you would compute when the source were at rest. Determine the wave speed?
ii) You are standing by the roadside as a truck approaches and you compute the dominant frequency in the truck noise at around 1120 Hz. As the truck passes, the frequency reduces to 920 Hz. Find out the speed of truck?