Let v be the wave's speed, λ its wavelength, and f its frequency. These quantities are related via the equation v = λ f. Note that, if the wave speed decreases, the wavelength must also decrease for the frequency to remain constant.

What is the wavelength λ of light in glass, if its wavelength in air is λ₀, its speed in air is c, and its speed in the glass is v? Express your answer in terms of λ₀, c, and v.

The index of refraction n for a material is defined to be n = c / v. Rewrite your answer from Part A in terms of the index of refraction. Express your answer in terms of λ₀ and n.