The wavelength of light coming from a sodium source is 589 nm. What will be its wavelength in water? Refractive index of water 1.33.`

Explanation

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

### Step 1: Understand the relationship
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 the medium. It can also be expressed in terms of wavelengths:
\[ n = \frac{\lambda_{\text{air}}}{\lambda_{\text{medium}}} \]
where:
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