Here are the essential concepts you must grasp in order to answer the question correctly.
Wavelength and Frequency
Wavelength is the distance between successive peaks of a wave, while frequency is the number of peaks that pass a point in a given time. In a vacuum, the speed of light is constant, and the relationship between wavelength (λ), frequency (f), and speed (c) is given by the equation c = λf. When light travels through different media, its speed changes, affecting its wavelength while the frequency remains constant.
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Refraction and Index of Refraction
Refraction is the bending of light as it passes from one medium to another due to a change in speed. The index of refraction (n) quantifies this change and is defined as the ratio of the speed of light in a vacuum to the speed of light in the medium. The relationship between the wavelength in a medium (λ') and the wavelength in a vacuum (λ) is given by λ' = λ/n, where n is the index of refraction of the medium.
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Speed of Light in Different Media
The speed of light varies in different materials due to their optical properties. In a vacuum, light travels at approximately 3.00 x 10^8 m/s, but in a medium like water or glass, it travels slower. The time taken for light to travel a certain distance in a medium can be used to calculate the speed of light in that medium, which is essential for determining the new wavelength when light enters a different substance.
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