Final answer:
Shafts of light falling at odd angles or colors in light used arbitrarily are caused by the phenomenon of dispersion.
Step-by-step explanation:
Shafts of light falling at odd angles or colors in light used arbitrarily are caused by the phenomenon of dispersion. When light passes through a prism, different colors (wavelengths) of light are bent at different angles. This creates a separation of colors, as seen in a rainbow or when light passes through a prism.