MCQ Detailed View

A periscope is an optical instrument that allows people, especially submariners, to see objects above the water surface while remaining submerged. It is extensively used in submarines and tanks for observation without exposing the observer to danger. The periscope works based on the principle of reflection of light using mirrors or prisms.

The instrument consists of a long tube with mirrors or prisms at each end. Light from the object above the water enters the top of the tube and is reflected downwards to the observer's eye at the bottom. This reflection allows the submarine crew to see distant objects, ships, or coastlines without surfacing. Modern periscopes may also include lenses, cameras, or digital displays for better clarity.

Other options in the question are incorrect:

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  Telescope is used to observe distant objects but is generally for astronomical or terrestrial viewing, not for submerged observation.

  
  


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  Kaleidoscope is a decorative optical instrument that creates symmetrical patterns and has no practical use for observation.

  
  


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  Spectroscope is used to analyze light spectra and identify elements, not for seeing objects physically.

  
  

Periscopes are critical in naval operations and for safety and strategic observation. Understanding its working helps students learn fundamental optics concepts like reflection, line of sight, and image formation.

In summary, the correct answer is Periscope, as it is the instrument specifically designed for a submarine to view objects above water while remaining safely submerged. Knowledge of periscopes also highlights how physics principles are applied in everyday technology and engineering.