Final answer:
White light refracts and disperses into its constituent colors when it enters a prism, with violet light bending the most and red light the least. Upon exiting the prism, light is further dispersed, creating a spectrum on a screen.
Step-by-step explanation:
When white light enters a prism, it experiences refraction, meaning the light path is bent due to a change in speed as it enters a different medium. The bending varies with the wavelength of light because different colors have different wavelengths, with violet light bending the most and red light the least. This process is known as dispersion and results in a spectrum of colors, ranging from red to violet, similar to a rainbow. Upon exiting the prism, the light is refracted again, causing the colors to spread out more if projected onto a screen, producing what is known as a continuous spectrum.