500 words about periscope
Answers
Answer:
Periscopes are still used today in tanks and some submarines. A simple periscope is just a long tube with a mirror at each end. The mirrors are fitted into each end of the tube at an angle of exactly 45 degrees (45°) so that they face each other.
Answer:
periscope is an instrument for observation over, around or through an object, obstacle or condition that prevents direct line-of-sight observation from an observer's current position.[1][2]
Principle of the periscope. The periscope on the left uses mirrors whereas the right uses prisms.
a Mirrors
b Prisms
c Observer's eye
Principle of the lens periscope. The two periscopes differ in the way they erect the image. The left one uses an erecting prism whereas the right uses an erecting lens and a second image plane.
a Objective lens
b Field lens
c Image erecting lens
d Ocular lens
e Lens of the observer's eye
f Right-angled prism
g Image-erecting prism
In its simplest form, it consists of an outer case with mirrors at each end set parallel to each other at a 45° angle. This form of periscope, with the addition of two simple lenses, served for observation purposes in the trenches during World War I. Military personnel also use periscopes in some gun turrets and in armoured vehicles.[1]