Final answer:
Waves that are 'blue shifted' indeed have shorter wavelengths than 'red shifted' waves, as a blue shift indicates that the source is moving closer, decreasing the wavelength, while a red shift means the source is moving away, increasing the wavelength.
Step-by-step explanation:
The statement that waves that are "blue shifted" have shorter wavelengths than those that are "red shifted" is true. A blue shift occurs when a wave source moves towards an observer, leading to a decrease in wavelength and an increase in frequency. Conversely, a red shift happens when the wave source moves away from an observer, resulting in an increase in wavelength and a decrease in frequency. In the context of visible light, a decrease in wavelength shifts the light towards the blue end of the spectrum, while an increase in wavelength shifts it towards the red end of the spectrum. This concept is rooted in the Doppler effect and is commonly used in astronomy to determine the movement of stars and galaxies relative to Earth.