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Which one of the following statements is not correct for light rays ?

Options

  1. ALight travels at different speeds in different media.
  2. BLight travels at almost 300 million metres per second in air.
  3. CLight speeds down as it leaves a water surface and enters the air.
  4. DLight speeds up as it leaves a glass surface and enters the air.

Correct answer

C. Light speeds down as it leaves a water surface and enters the air.

Step-by-step solution

A light ray is a line (straight or curved) that is perpendicular to the light's wavefronts; its tangent is collinear with the wave vector. Light rays in homogeneous media are straight. They bend at the interface between two dissimilar media and may be curved in a medium in which the refractive index changes Light waves travel fastest through a vacuum and air, and slower through other materials such as glass or water. Light travels at approximately 300,000 kilometers per second in a vacuum, which has a refractive in

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