Question

waves with longer wavelengths travel at greater speeds in a material than waves with shorter wavelengths. therefore, when entering a material, red light with its wavelengths travels faster and less than violet light with its wavelengths. need help? review these concept resources.

Explanation:

The problem is about the properties of light waves (red and violet) in a material. Red light has longer wavelengths than violet light. When light enters a material, the refractive index \(n=\frac{c}{v}\) (where \(c\) is the speed of light in vacuum and \(v\) is the speed in the material). Since \(v\) is greater for longer - wavelength light (red), and \(n=\frac{\sin\theta_1}{\sin\theta_2}\) (Snell's law, \(\theta_1\) is the angle of incidence and \(\theta_2\) is the angle of refraction). A lower refractive index (\(n\)) for red light (because \(v\) is larger, \(n = c/v\) is smaller) means that red light bends (refracts) less than violet light.

Answer:

longer; refracts; shorter