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प्रश्न
State two advantages and two disadvantages of the reflecting periscope.
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उत्तर
Advantages of Reflecting Periscope:
- It is used to see above the head of crowds.
- It is used by soldiers in trench warfare.
Disadvantages of Reflecting Periscope:
- The final images is not brightly illuminated as light energy is absorbed due to two successive reflections.
- Any deposition of moisture of dust on the mirror reduces the reflection almost to nil, and hence, the periscope cannot be used in places where there is a lot of dust or moisture.
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