Models use familiar objects to represent unfamiliar things. Models can help you visualize, or picture in your mind, something that is difficult to see or understand. Models can help scientists communicate their ideas, understand processes, and make predictions.
When white light splits into the spectrum of colors of which it is composed, it is said to have undergone dispersion. Dispersion happens when white light gets separated into colors based on the wavelength of the light. Due to dispersion of light, people can see a rainbow in the sky. I hope the answer helps.