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Question
Explain the working of a periscope.
Solution
Periscope:
- It is an instrument used for viewing bodies or ships, which are over and around another body or a submarine.
- It is based on the principle of the law of reflection of light.
- It consists of a long outer case and inside this case mirrors or prisms are kept at each end, inclined at an angle of 45°.
- Light coming from the distant body falls on the mirror at the top end of the periscope and gets reflected vertically downward.
- This light is reflected again by the second mirror kept at the bottom, so as to travel horizontally and reach the eye of the observer.
- In some complex periscopes, optic fiber is used instead of mirrors for obtaining a higher resolution.
- The distance between the mirrors also varies depending on the purpose of using
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