Choose the Correct Alternative and Rewrite the Following: Always like a Concave Lens - Science and Technology 1

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MCQ

Choose the correct alternative and rewrite the following: 

Inside water, an air bubble behaves ....................

Options

  • always like a flat plate

  • always like a concave lens

  • always like a convex lens

  • always like a concave mirror

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Solution

always like a concave lens

  • Inside water, the air bubble behaves like a Concave lens. The concave lenses are known as diverging lenses as the rays diverge after falling on the concave lens.
  • The concave lens diverges a straight light beam coming from the source to a diminished, upright, virtual image and forms both real and virtual images.
  • The air bubble is a sphere with a convex surface and when light reaches it, the light is reflected within the water as in a concave lens.

The refractive index of air = 1 and

The index of water = 1.33.

Since the water refractive index is greater than air, the air bubbles in the water will behave like a concave lens.

Concept: Concave Lens
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2014-2015 (July)

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