- The speed of light changes as it passes from one medium to another. - Light travels fastest in a vacuum (approximately 3 x 10⁸ m/s). - The speed of light is slower in optically denser media (like water or glass) than in optically less dense media (like air or vacuum).
Which one of the following statements is *not* correct for light rays ?
Asked in UPSC NDA 1 2021 · Topic: Optics (Reflection and Refraction at plane and spherical surfaces)
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Answer: C. Light speeds down as it leaves a water surface and enters the air.
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