In optical fibres, the refractive index of the core is
- greater than that of the cladding
- equal to that of the cladding
- smaller than that of the cladding
- independent of that of the cladding
The Correct Option is A
Solution and Explanation
Top Questions on Ray optics and optical instruments
- Given below are two statements:
Statement 1: Image formation needs regular reflection and/or refraction.
Statement 2: The variety in colour of objects we see around us is due to the constituent colours of the light incident on them.
In the light of the above statements, choose the most appropriate answer from the options given below :- NEET (UG) - 2024
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- An effective power of a combination of 5 identical convex lenses which are kept in contact along the principal axis is 25 D. Focal length of each of the convex lens is :
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- The position of the image formed by the combination of lenses is :
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- Given below are two statements:
Statement (I): When an object is placed at the centre of curvature of a concave lens, image is formed at the centre of curvature of the lens on the other side.
Statement (II): Concave lens always forms a virtual and erect image.
In the light of the above statements, choose the correct answer from the options given below:- JEE Main - 2024
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- If the distance between object and its two times magnified virtual image produced by a curved mirror is 15 cm, the focal length of the mirror must be :
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Concepts Used:
Ray Optics and Optical Instruments
Optics, deals with the determination of behaviour and the properties of light, along with its interactions with the matter and also with the instruments that are used to detect it.
Ray optics is also known as the geometrical optics and it is a branch of science which describes light propagation.
Reflection is the change in direction of light at an interface in-between two different media so that the wave-front returns into a medium from which it was originated.
Speed of light is the rate at which the light travels in free space.
A phenomenal change in image formed when the light is passed from one medium to another which is called Refraction.
Total Internal Reflection is the reflection of light when the light ray enters into a rarer medium from a denser medium and the angle of incidence is higher than the critical angle of incidence then that light ray will be reflected back to the denser medium.
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