Which one of the following remains unchanged when light waves enter water from air?
Show Hint
- Wavelength
- Wavenumber
- Frequency
- Intensity
The Correct Option is C
Solution and Explanation
When light enters a new medium, such as water from air, its speed changes, which affects its wavelength. However, the frequency of the light remains constant because the frequency is determined by the source of the light, not the medium.
Step 2: Analyzing the options.
(A) Wavelength: Incorrect — The wavelength changes as the speed of light changes in different media.
(B) Wavenumber: Incorrect — The wavenumber is inversely proportional to the wavelength and therefore changes.
(C) Frequency: Correct — The frequency of the light remains unchanged when it enters a new medium.
(D) Intensity: Incorrect — The intensity can change depending on the properties of the medium.
Step 3: Conclusion.
The correct answer is (C) Frequency, as the frequency of light remains constant when it enters a new medium.
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