Pick up the correct statement from the following: (A) Spherical aberration may be reduced by diminishing the aperture (B) Spherical aberration may be minimised by replacing the single lens by a combination of the lenses (C) In telescope objectives, a combination of convex lens and concave lens is used (D) All the above

Pick up the correct statement from the following:
(A) Spherical aberration may be reduced by diminishing the aperture
(B) Spherical aberration may be minimised by replacing the single lens by a combination of the
lenses
(C) In telescope objectives, a combination of convex lens and concave lens is used
(D) All the above
by

1 Answer

Answer :

(D) All the above
by

Related questions

A lens or combination of lenses in which the following defect is completely eliminated is called aplanatic (A) Spherical aberration (B) Chromatic aberration (C) Coma (D) Astigmatism

Description : A lens or combination of lenses in which the following defect is completely eliminated is called aplanatic (A) Spherical aberration (B) Chromatic aberration (C) Coma (D) Astigmatism

Last Answer : (A) Spherical aberration

Pick up the correct statement from the following: (A) A refracting telescope consists optically of two lenses (B) The principal axes of both the lenses coincide the optical axis of the telescope(C) The lens nearer the object to be viewed is convex and is called objective (D) All the above

Description : Pick up the correct statement from the following: (A) A refracting telescope consists optically of two lenses (B) The principal axes of both the lenses coincide the optical axis of the telescope (C) The lens nearer the object to be viewed is convex and is called objective (D) All the above

Last Answer : (D) All the above

Two concave lenses of 60 cm focal length are cemented on either side of a convex lens of 15 cm focal length. The focal length of the combination is (A) 10 cm (B) 20 cm (C) 30 cm (D) 40 cm

Description : Two concave lenses of 60 cm focal length are cemented on either side of a convex lens of 15 cm  focal length. The focal length of the combination is  (A) 10 cm  (B) 20 cm  (C) 30 cm  (D) 40 cm 

Last Answer : (C) 30 cm 

An internal focussing type surveying telescope, may be focussed by the movement of (A) Objective glass of the telescope (B) Convex-lens in the telescope (C) Concave lens in the telescope (D) Plano-convex lens in the telescope

Description : An internal focussing type surveying telescope, may be focussed by the movement of  (A) Objective glass of the telescope  (B) Convex-lens in the telescope  (C) Concave lens in the telescope  (D) Plano-convex lens in the telescope

Last Answer : (C) Concave lens in the telescope 

Ramsden eye-piece consists of (A) Two convex lenses short distance apart (B) Two concave lenses short distance apart (C) One convex lens and one concave lens short distance apart (D) Two Plano-convex lenses short distance apart, with the convex surfaces facing each other

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Last Answer : (D) Two Plano-convex lenses short distance apart, with the convex surfaces facing each other

Based on the diagram shown, what kind of lenses would Sumati need to make the telescope? (a) Concave lenses (b) Convex lenses (c) Bifocal lenses

Description : Based on the diagram shown, what kind of lenses would Sumati need to make the telescope? (a) Concave lenses (b) Convex lenses (c) Bifocal lenses

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Which one of the following lenses should be used to correct the defect of astigmatism? (1) Cylindrical lens (2) Concave lens (3) Convex lens (4) Bifocal lens

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Last Answer : (1) Cylindrical lens Explanation: Astigmatism is an optical defect in which vision is blurred due to the inability of the optics of the eye to focus a point object into a sharp focused image ... lens, and cannot be corrected by standard spectacle lenses, but can be corrected by contact lenses.

Which one of the following lenses should be used to correct the defect of astigmatism ? (1) Cylindrical lens (2) Concave lens (3) Convex lens (4) Bifocal lens

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Pick up the correct statement from the following: (A) The power of a lens is the reciprocal of its focal length (B) The unit of power of the lens is Diopter (C) The power of two or more thin lenses in contact is the power of the combination of the lenses (D) All the above

Description : Pick up the correct statement from the following:  (A) The power of a lens is the reciprocal of its focal length  (B) The unit of power of the lens is Diopter  (C) The power of two or more thin lenses in contact is the power of the combination of the  lenses  (D) All the above 

Last Answer : (D) All the above 

Pick up the correct specification of Ramsden eyepiece from the following: (A) It consists of two equal piano convex lenses (B) The curved surfaces of Plano-convex lenses face each other (C) The distance between the diaphragm and the front lens of the eyepiece is kept equal to 1/4 th of the focal length of a lens so that rays from a point on the diaphragm enter the eye as a parallel beam (D) All the above

Description : Pick up the correct specification of Ramsden eyepiece from the following:  (A) It consists of two equal piano convex lenses  (B) The curved surfaces of Plano-convex lenses face each other  (C) ... from a point on the diaphragm enter the eye as a  parallel beam  (D) All the above 

Last Answer : (D) All the above 

The defect of a lens whereby rays of white light proceeding from a point get dispersed into their components and conveyed to various foci, forming a blurred and coloured image is known as (A) Chromatic aberration (B) Spherical aberration (C) Astigmatism (D) Coma

Description : The defect of a lens whereby rays of white light proceeding from a point get dispersed into their components and conveyed to various foci, forming a blurred and coloured image is known as (A) Chromatic aberration (B) Spherical aberration (C) Astigmatism (D) Coma

Last Answer : (A) Chromatic aberration

What is a compound microscope? (1) A microscope that has one lens. (2) A microscope that has two sets of lenses : an occular lens and an eyepiece. (3) A microscope whose lenses are concave. (4) A microscope whose lenses are convex.

Description : What is a compound microscope? (1) A microscope that has one lens. (2) A microscope that has two sets of lenses : an occular lens and an eyepiece. (3) A microscope whose lenses are concave. (4) A microscope whose lenses are convex.

Last Answer : (2) A microscope that has two sets of lenses : an occular lens and an eyepiece. Explanation: A compound microscope is a microscope which uses multiple lenses to collect light from the ... lens provides the primary magnification which is compounded (multiplied) by the ocular lens (eyepiece).

Based on the diagram shown, what kind of lens is used to make the overhead projector? (a) concave lenses (b) convex lenses (c) bifocal lenses (d) flat lenses

Description : Based on the diagram shown, what kind of lens is used to make the overhead projector? (a) concave lenses (b) convex lenses (c) bifocal lenses (d) flat lenses

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What is lens? Explain the difference between convex and concave lenses.

Description : What is lens? Explain the difference between convex and concave lenses.

Last Answer : Lens: A lens is a piece of glass or other transparent material like plastic whose one or both side is spherical. Types There are two types of lenses. 1. Convex lens 2. Concave lens Convex lens ... thinner at the edges. Concave lens Concave lens is thinner in the middle and thicker at the edges.

What is a compound microscope? (1) A microscope that has one lens. (2) A microscope that has two sets of lenses : an occular lens and an eyepiece. (3) A microscope whose lenses are concave. (4) A microscope whose lenses are convex.

Description : What is a compound microscope? (1) A microscope that has one lens. (2) A microscope that has two sets of lenses : an occular lens and an eyepiece. (3) A microscope whose lenses are concave. (4) A microscope whose lenses are convex.

Last Answer : A microscope that has two sets of lenses : an occular lens and an eyepiece.

During accommodation for near: a. the spherical aberration of the eye increases b. the ciliary muscle relaxes c. the field of vision decreases d. the amount of light entering the eye increases e. the thickness of the lens increases

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A concave lens is kept in contact with a convex lens of focal length `20 cm`. The combination works as a converging lens of focal length `100 cm`. Cal

Description : A concave lens is kept in contact with a convex lens of focal length `20 cm`. The combination works as a converging lens of focal length `100 cm`. Cal

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A compound lens has been formed by joinined a convex and a concave lens, each of focal length 30 cm. what is the focal length of the combination? What

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A real image can be formed by which of the following single mirrors? w) a plane mirror x) a concave spherical mirror y) a convex spherical mirror

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A virtual image can be formed by one or more of the following single mirrors? Identify them. w) plane mirror x) concave spherical mirror y) convex spherical mirror z) all of the above

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Pick up the correct statement from the following: (A) The cost of square rooms is less (B) The expenditure on the foundation and roof for the double storeyed building is nearly half of that for the ground storeyed building (C) The cost of construction of a house may be minimised by restricting the height floors (D) All the above

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Pick up the correct statement from the following: (A) The diaphragm is placed between eyepiece and the objective but nearer to the former (B) The diaphragm is placed between the eyepiece and objective but nearer to the later (C) The outer component of the objective is a double-convex lens of crown glass (D) All the above

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The power of a lens (A) Is reciprocal of its focal length (B) Is positive if it is a convex lens (C) Is negative if it is a concave lens (D) Is measured in Diopter

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Last Answer : (D) Is measured in Diopter

Flint glass (A) Has slightly the greater refracting power than crown glass (B) Has roughly double refracting power than that of crown (C) And crown glass proportions yield the required focal length and neutralise the dispersion produced by the convex lens at the emergence from the concave (D) All the above

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In Fresnel diffraction A. source of light is kept at infinite distance from the aperture B. source of light is kept at finite distance from the aperture C. Convex lens used D. aperture width is selected so that it can acts as a point source

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Which lenses are used by people having short-sightedness? A. Convex B. Concave (Answer) C. Concavo-convex D. Plain

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Which among the following lens is used to correct Presbyopia? (1) Concave (2) Convex (3) Cylindrical (4) Bifocal

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What type of lens is used to correct vision of a person suffering from Myopia? (1) Convex lens (2) Concave lens (3) Crossed lens (4) Cylindrical lens

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Last Answer : (2) Concave lens Explanation: Near-sightedness, also known as short-sightedness and myopia, is a condition of the eye where light focuses in front of, instead of on, the retina. This causes distant objects to be blurry while close objects appear normal.

What type of lens is used to correct vision of a person suffering from Myopia? (1) Convex lens (2) Concave lens (3) Crossed lens (4) Cylindrical lens

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The type of mirror used in the headlamps of cars is the (a) plane mirror (b) spherical convex mirror (c) spherical concave mirror (d) parabolic concave mirror

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The type of mirrors used in the headlamp of cars is – (1) Parabolic concave (2) Plane (3) Spherical convex (4) Cylindrical concave

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Last Answer : (1) Parabolic concave Explanation: Curved mirror that reflects light from its inner surface, the curve being inward. It may be either circular or parabolic in section. A concave mirror converges parallel light ... is not too close to the mirror. A real image is formed at the point of convergence.

The type of mirrors used in the headlamp of cars is (1) parabolic concave (2) plane (3) spherical convex (4) cylindrical concave

Description : The type of mirrors used in the headlamp of cars is (1) parabolic concave (2) plane (3) spherical convex (4) cylindrical concave

Last Answer : parabolic concave

Draw the ray diagram in each case to show the position and nature of the image formed when the object is placed: (i) at the centre of curvature of a concave mirror (ii) between the pole P and focus F of a concave mirror (iii) in front of a convex mirror (iv) at 2F of a convex lens (v) in front of a concave lens -Physics

Description : Draw the ray diagram in each case to show the position and nature of the image formed when the object is placed: (i) at the centre of curvature of a concave mirror (ii) between the pole P and focus F of ... front of a convex mirror (iv) at 2F of a convex lens (v) in front of a concave lens -Physics

Last Answer : Answer. Nature of image: Real, inverted and same size image is formed at the centre of curvature. Nature of image: Virtual, enlarged and erect image is formed behind the mirror. Nature of image: Virtual ... : Virtual, erect and diminished image is formed between O and F on the same side of object.

Ray coming from an object situated at infinity, fall on a convex lens and an image is formed at a distance of 16 cm from the lens. When a concave lens

Description : Ray coming from an object situated at infinity, fall on a convex lens and an image is formed at a distance of 16 cm from the lens. When a concave lens

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Find the focal length and power of a convex lens, which when placed in contact with a concave lens of focal length `25 cm` forms a real image `5` time

Description : Find the focal length and power of a convex lens, which when placed in contact with a concave lens of focal length `25 cm` forms a real image `5` time

Last Answer : Find the focal length and power of a convex lens, which when placed in contact with a concave ... the object placed `20 cm` from the combination.

The focal length of a concave-convex lens of radii of curvature 5 cm and 10 cm is 20 cm. what will be its focal length in water ? Given `.^(a)mu_(w) =

Description : The focal length of a concave-convex lens of radii of curvature 5 cm and 10 cm is 20 cm. what will be its focal length in water ? Given `.^(a)mu_(w) =

Last Answer : The focal length of a concave-convex lens of radii of curvature 5 cm and 10 cm is 20 cm. what will be its ... water ? Given `.^(a)mu_(w) = 4//3`.

Which one of the following can be used to focus sunlight? A. Plane mirror B. Concave lens C. Concave mirror D. Convex mirror

Description : Which one of the following can be used to focus sunlight? A. Plane mirror B. Concave lens C. Concave mirror D. Convex mirror

Last Answer : ANSWER: C

When light enters a closed room through a small hole in the door, the image of an outside building appears as inverted on the opposite wall. This is because (a) The hole acts as a convex lens (b) Light takes curvature at the edges of the hole (c) Of rectilinear propagation of light (d) The hole acts as a concave lens

Description : When light enters a closed room through a small hole in the door, the image of an outside building appears as inverted on the opposite wall. This is because (a) The hole acts as a convex lens (b) ... the edges of the hole (c) Of rectilinear propagation of light (d) The hole acts as a concave lens

Last Answer : Ans:(b)

Which of the following can be used as a burning glass? (a) Plane mirror (b) Convex mirror (c) Concave lens (d) Concave mirror

Description : Which of the following can be used as a burning glass? (a) Plane mirror (b) Convex mirror (c) Concave lens (d) Concave mirror

Last Answer : Ans:(d)

Which one of the following is used to remove Astigmatism for a human eye? (1) Concave lens (2) Convex lens (3) Cylindrical lens (4) Prismatic lens

Description : Which one of the following is used to remove Astigmatism for a human eye? (1) Concave lens (2) Convex lens (3) Cylindrical lens (4) Prismatic lens

Last Answer : (3) Cylindrical lens Explanation: In Astigmatism, eye cannot see objects in two orthogonal directions clearly simultaneously. This abnormality is removed by using cylindrical lens.

Vehicles use ______ to see the objects coming from behind. (1) Concave lens (2) Convex lens (3) Convex mirror (4) Concave mirror

Description : Vehicles use ______ to see the objects coming from behind. (1) Concave lens (2) Convex lens (3) Convex mirror (4) Concave mirror

Last Answer : (2) Convex lens Explanation: Convex mirror is used in rear view mirror of vehicles; so that the driver can see the traffic coming from behind. The field of view is widest in case of a convex mirror, which enables it to show a wider area from behind.

Persons suffering from myopia are advised to use – (1) convex lens (2) concave lens (3) piano-convex lens (4) plano-concave lens

Description : Persons suffering from myopia are advised to use – (1) convex lens (2) concave lens (3) piano-convex lens (4) plano-concave lens

Last Answer : (2) concave lens Explanation: A concave lens is used to correct short-sightedness (myopia). In myopia, images are formed in front of the retina, resulting in a blurred image. This occurs when the ... too long or the refractive powers of the cornea and lens of the eye are relatively too strong.

Magnifying Glass is basically a – (1) Plano-concave lens (2) Concave lens (3) Convex lens (4) Cylindrical lens

Description : Magnifying Glass is basically a – (1) Plano-concave lens (2) Concave lens (3) Convex lens (4) Cylindrical lens

Last Answer : (3) Convex lens Explanation: A magnifying glass is a convex lens that is used to produce a magnified image of an object. The magnification of a magnifying glass depends upon where it is placed between the user's eye and the object being viewed, and the total distance between them.

`Short-sight' in human eye can be corrected by using proper – (1) convex lens (2) concave lens (3) cylindrical lens (4) bifocal lens

Description : `Short-sight' in human eye can be corrected by using proper – (1) convex lens (2) concave lens (3) cylindrical lens (4) bifocal lens

Last Answer : (2) concave lens Explanation: Scintillation or twinkling is generic terms for variations in apparent brightness or position of a distant luminous object viewed through a medium. If ... is termed astronomical scintillation; within the atmosphere, the phenomenon is termed terrestrial scintillation.

A camera uses a ______ to form an image on a piece of film at the back. (1) convex lens (2) concave lens (3) diverging lens (4) none of these

Description : A camera uses a ______ to form an image on a piece of film at the back. (1) convex lens (2) concave lens (3) diverging lens (4) none of these

Last Answer : (1) convex lens Explanation: A camera consists of three main parts. • The body which is light tight and contains all the mechanical parts. • The lens which is a convex lens. • The film or a charged couple device in the case of a digital camera.

Spectacles used for viewing 3D films have – (1) Bifocal lens (2) Convex lens (3) Concave lens (4) Polaroid

Description : Spectacles used for viewing 3D films have – (1) Bifocal lens (2) Convex lens (3) Concave lens (4) Polaroid

Last Answer : (4) Polaroid Explanation: A polarized 3D system uses polarization glasses to create the illusion of three-dimensional images by restricting the light that reaches each eye, an example of stereoscopy. ... and blocks the light polarized in the opposite direction, each eye sees a different image.

A simple microscope consists of : (1) a short focus convex lens (2) a long focus convex lens (3) a short focus concave lens (4) a long focus concave lens

Description : A simple microscope consists of : (1) a short focus convex lens (2) a long focus convex lens (3) a short focus concave lens (4) a long focus concave lens

Last Answer : (1) a short focus convex lens Explanation: Simple microscope - light microscope consisting of a short focus single convex lens is used to produce an enlarged image. The magnifying glass was ... object viewed and one lens, increasing the visibility of the object by some amount (magnification).

Which one of the following is used to remove Astigmatism for a human eye? (1) Concave lens (2) Convex lens (3) Cylindrical lens (4) Prismatic lens

Description : Which one of the following is used to remove Astigmatism for a human eye? (1) Concave lens (2) Convex lens (3) Cylindrical lens (4) Prismatic lens

Last Answer : (3) Cylindrical lens Explanation: A cylindrical lens is a lens which focuses light into a line instead of a point, as a spherical lens would.