A diver under water, looks obliquely at a fisherman standing on the bank of a lake. Would the fisherman look taller or shorter to the diver than what he actually is? - Physics

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Short Note

A diver under water, looks obliquely at a fisherman standing on the bank of a lake. Would the fisherman look taller or shorter to the diver than what he actually is?

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Solution

The diver is in the water and the fisherman is on land (i.e., in the air). Water is a denser medium than air. It is given that the diver is viewing the fisherman. This indicates that the light rays are travelling from a denser medium to a rarer medium. Hence, the refracted rays will move away from the normal. As a result, the fisherman will appear to be taller.

Concept: Refraction
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Chapter 9: Ray Optics and Optical Instruments - Exercise [Page 346]

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NCERT Physics Class 12
Chapter 9 Ray Optics and Optical Instruments
Exercise | Q 9.18 (c) | Page 346
NCERT Physics Class 12
Chapter 9 Ray Optics and Optical Instruments
Exercise | Q 18.3 | Page 347

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