What does periscope mean?
What does periscope mean?
A 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. In its simplest form, it consists of an outer case with mirrors at each end set parallel to each other at a 45° angle.
What is a periscope easy definition?
A periscope is an optical instrument that uses a system of prisms, lenses or mirrors to reflect images through a tube. Light from a distant object strikes the top mirror and is then reflected at an angle of 90 degrees down the periscope tube.
What does periscope mean in reading?
English Language Learners Definition of periscope : a long tube that contains lenses and mirrors and that is used to look over or around something and especially by a person in a submarine to see above the surface of the water.
What is periscope used for?
Periscope, optical instrument used in land and sea warfare, submarine navigation, and elsewhere to enable an observer to see his surroundings while remaining under cover, behind armour, or submerged.
Where are periscopes used today?
Uses Of Periscope
- It is used in submarines to determine the distance of a torpedo and helps in deciding the right time for the attack.
- It is used in a nuclear reactor to observe the chemical reactions that are taking place.
- In military periscopes are used to observe from their hiding position.
What mirror is used for periscope?
plane mirrors
What is the mirror formula?
Suppose an object is placed u cm in front of a spherical mirror of focal length f such that the image is formed v cm from the mirror, then u, v and f are related by the equation; 1/f= 1/u + 1/v. This equation is referred to as the mirror formula. The formula holds for both concave and convex mirrors.
What is V and U in light?
Where v is the image distance and u is the object distance. Hence, the expression for magnification (m) becomes: m = h’/h = -v/u. Learn more about Reflection of Light here.
In which mirror image is always erect?
Convex mirror
Is U positive in concave mirror?
Any distances measured on that side are positive. Distances measured on the other side are negative. f, the focal length, is positive for a concave mirror, and negative for a convex mirror. When the image distance is positive, the image is on the same side of the mirror as the object, and it is real and inverted.
What is the sign of concave mirror?
Since, object is always placed in front of the mirror hence the sign of object is taken as negative. Since, the centre of curvature and focus lie in front of the concave mirror, so signs of radius of curvature and focal length are taken as negative in the case of concave mirror.
What is U in concave mirror?
The distance between the object and the pole of the mirror is called the object distance(u). The distance between the image and the pole of the mirror is called Image distance(v). The distance between the Principal focus and pole of the mirror is called Focal Length(f).
What is the applications of concave lens?
A concave lens is used to diverge incident rays. This helps to create a virtual image on the opposite side of the refracting surface. Hence, these lenses are used in binoculars, telescopes, cameras, flashlights and eyeglasses.
What is another name of convex lens?
converging lens
What is the another name of concave mirror?
converging mirrors
Where do we use concave mirrors?
Concave mirrors are used as searchlights, shaving mirrors, satellite dishes, and many more. These mirrors have the property to collimate and concentrate light rays. Concave mirrors in torches and headlights are used as reflectors.
Which are the places where mirror is used?
Mirrors commonly are placed in the bathroom or bedroom for the practical use of checking out your or your outfit while getting ready. Mirrors can be used in other parts of the home too. You can place a mirror in the hallway to make the smaller space appear larger.