Light coming from a sodium lamp has a wavelength of 632 nm. What will be its wavelength in water? Take refractive index of water = 1.33.

Explanation

To find the wavelength of light in water, we can use the relationship between the wavelength of light in different media and the refractive index of the medium. Here’s a step-by-step solution:

### Step 1: Understand the relationship between wavelength and refractive index
The refractive index (n) of a medium is defined as the ratio of the speed of light in vacuum (or air) to the speed of light in that medium. It can also be expressed in terms of the wavelengths in air (λ_air) and in the medium (λ_medium):
\[ n = \frac{\lambda_{\text{air}}}{\lambda_{\text{medium}}} \]

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