## College Physics (4th Edition)

The wavelength of the light in water is $0.375~\mu m$
We can find the index of refraction in water: $v_{water} = \frac{c}{n}$ $n = \frac{c}{v_{water}}$ $n = \frac{c}{0.750~c}$ $n = 1.333$ We can find the wavelength in water: $\lambda_{water} = \frac{\lambda_{air}}{n}$ $\lambda_{water} = \frac{0.500~\mu m}{1.333}$ $\lambda_{water} = 0.375~\mu m$ The wavelength of the light in water is $0.375~\mu m$.