2006-06-19 18:47:22 · 5 answers · asked by agnes j 1 in Education & Reference ➔ Primary & Secondary Education
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periscope is an instrument for observation from a concealed position. In its simplest form it is a tube in each end of which are mirrors set parallel to each other and at an angle of 45° with respect to the line between them. It may be used as a toy or for seeing over people's heads in a crowd. This form of periscope, with the addition of two simple lenses, was used for observation purposes in the trenches during World War I.
A modern submarine periscope incorporates lenses for magnification and functions as a telescope. It typically employs prisms and total internal reflection instead of mirrors, because prisms, which do not require coatings on the reflecting surface, are much more rugged than mirrors. It may have additional optical capabilities such as range finding and targeting. The mechanical systems of submarine periscopes are typically hydraulically powered and need to be quite sturdy to withstand the drag through water. The periscope chassis may also be used as to support a radio or radar antenna.
Submarines traditionally had two periscopes: a navigation periscope and a targeting, or commander's, periscope. These were originally mounted one forward of the other in the narrow hulls of diesel-electric submarines. In the much wider hulls of recent US Navy submarines, they are located side-by-side.
2006-06-19 19:01:55 · answer #1 · answered by mallimalar_2000 7 · 1⤊ 0⤋
the concept of a periscope is to be able to see around corners, or above you, this is done by bouncing the image you want to see off of strategically placed mirrors.
2006-06-19 18:55:40 · answer #2 · answered by ♫jmann♫ 5 · 0⤊ 0⤋
Generally and simply, a tube having two mirrors in it. One at the bottom, cantered at 45' and one at the top also at 45' but aligned so the bottom one reflects what is seen in the top one. Then there are two holes in the tube. One at the bottom to look in to the bottom mirror at the reflected image from the top mirror and one on the opposite side at the top to reflect the "view" down to the bottom and out the site hole.
2006-06-19 18:58:50 · answer #3 · answered by Dusty 7 · 0⤊ 0⤋
Two mirrors, one on each end of a tube, placed at an angle such that the reflection of one mirror on one end can be seen on the other mirror at the other end.
2006-06-19 18:56:31 · answer #4 · answered by Melvin 4 · 0⤊ 0⤋
light refraction
2006-06-19 18:54:20 · answer #5 · answered by cowsformeatandmilk 4 · 0⤊ 0⤋