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Question
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
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.
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RELATED QUESTIONS
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Fill in the following blank with suitable word:
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