For a simple converging lens of ordinary glass, the focal length for red light is related to the focal length (call it f_b) for blue light by the relation

Question

Quizplus · Accepted Answer

The focal length for red light is larger than for blue light because red light has a longer wavelength and is less refracted by the lens than blue light, which has a shorter wavelength and is more refracted. This phenomenon is due to the dispersion of light, where different wavelengths of light are refracted by different amounts.

For a Simple Converging Lens of Ordinary Glass, the Focal