How does the frequency of a beam of ultra-violet light change when it ...
The frequency of light depends on the source of light and remains the same during refraction. The speed of the light changes when a ray of light passes from one medium to another. The speed of light is higher in a rarer medium than a denser medium. A ray of light travelling from a rarer medium to a denser medium slows down, due to which there is a change in the wave-length.
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How does the frequency of a beam of ultra-violet light change when it ...
When a beam of ultraviolet (UV) light travels from air into glass, the frequency of the light remains the same. This means that option 'c' is the correct answer.
To understand why the frequency does not change, let's first define frequency. Frequency is the number of wave cycles that pass a given point in one second. In other words, it is a measure of how many times a wave oscillates up and down in a given time period.
When light travels from one medium to another, such as from air to glass, its speed and wavelength change, but its frequency remains constant. This is known as the principle of constant frequency.
When light enters a denser medium, such as glass, it slows down. This change in speed is due to the interaction between the light waves and the atoms or molecules of the medium. However, the number of wave cycles that pass a given point in one second remains the same.
To visualize this, imagine a series of waves moving through air towards a glass surface. As the waves enter the glass, they slow down and their wavelength decreases. The distance between two neighboring wave peaks becomes shorter. However, the number of wave peaks passing a fixed point per unit of time remains unchanged. This means that the frequency remains constant.
The reason for this can be explained by the wave equation, which states that the product of frequency and wavelength is equal to the speed of light. Since the speed of light changes when it enters a different medium, either the frequency or the wavelength must change to maintain this equation. In the case of light entering glass, it is the wavelength that changes, while the frequency remains the same.
In summary, when a beam of ultraviolet light travels from air into glass, the frequency of the light remains constant. The change in speed and wavelength is compensated by keeping the frequency the same.
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