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

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
by

1 Answer

Answer :

(A) Spherical aberration
by

Related questions

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

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

Description : 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 ... telescope objectives, a combination of convex lens and concave lens is used (D) All the above

Last Answer : (D) All the above

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

Description : 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

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

Description : 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

Last Answer : Cylindrical lens

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

Description : 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

Last Answer : the thickness of the lens increases

Refracting telescopes, if uncorrected, suffer from chromatic aberration. Chromatic aberration occurs because: w) red light is focused more strongly than blue light x) blue light is focused more strongly than red light y) the outer light rays are focused more strongly than the central rays, z) the central light rays are focused more strongly than the outer rays.

Description : Refracting telescopes, if uncorrected, suffer from chromatic aberration. Chromatic aberration occurs because: w) red light is focused more strongly than blue light x) blue light is focused more strongly than ... central rays, z) the central light rays are focused more strongly than the outer rays.

Last Answer : ANSWER: X -- BLUE LIGHT IS FOCUSED MORE STRONGLY THAN RED LIGHT 

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 

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 

Among the defects of eye, the shortsightedness is called - (1) coma (2) hypermetropia (3) myopia (4) astigmatism

Description : Among the defects of eye, the shortsightedness is called - (1) coma (2) hypermetropia (3) myopia (4) astigmatism

Last Answer : (3) myopia Explanation: Myopia, commonly known as being nearsighted and shortsighted. It is a condition of the eye where the light that comes in does not directly focus on the retina but in ... . It may also be corrected by refractive surgery, though there are cases of associated side effects.

Among the defects of eye, the shortsightedness is called (1) coma (2) hypermetropia (3) myopia (4) astigmatism

Description : Among the defects of eye, the shortsightedness is called (1) coma (2) hypermetropia (3) myopia (4) astigmatism

Last Answer : myopia

Chromatic dispersion can be eliminated by __________. ∙ A. using a monochromatic light source ∙ B. using a very small numerical aperture fiber ∙ C. using a graded-index fiber ∙ D. using a very sensitive photo detector

Description : Chromatic dispersion can be eliminated by __________. ∙ A. using a monochromatic light source ∙ B. using a very small numerical aperture fiber ∙ C. using a graded-index fiber ∙ D. using a very sensitive photo detector

Last Answer : A. using a monochromatic light source

Large astronomical telescopes always use as objective (a) Lens (b) Mirror (c) Combination of lenses (d) None of the above

Description : Large astronomical telescopes always use as objective (a) Lens (b) Mirror (c) Combination of lenses (d) None of the above

Last Answer : Ans:(a)

Can astigmatism be corrected by lenses during cataract surgery?

Description : Can astigmatism be corrected by lenses during cataract surgery?

Last Answer : What's possible in today's world of eyecare is simply amazing. There are now specialty lenses that treat astigmatism that are used after cataract surgery, effectively improving the patient's vision.

The Huygens telescope eye piece (A) Is aplanatic (B) Achromatic (C) Both (a) and (b) (D) Neither (a) nor (b)

Description : The Huygens telescope eye piece (A) Is aplanatic (B) Achromatic (C) Both (a) and (b) (D) Neither (a) nor (b)

Last Answer : (C) Both (a) and (b)

Which one of the following statements is not correc t? (a) Parallax error is eliminated when there is no change in the staff reading when eye is moved up and down (b) The objective lens is to be focused towards a white or bright background for clear visibility of cross-hairs (c) Temporary adjustments of the dumpy level are to be performed at every set up (d) The eyepiece need not be adjusted after the first set up when the same surveyor is taking readings

Description : Which one of the following statements is not correc t? (a) Parallax error is eliminated when there is no change in the staff reading when eye is moved up and down (b) The objective lens is ... (d) The eyepiece need not be adjusted after the first set up when the same surveyor is taking readings

Last Answer : (b) The objective lens is to be focused towards a white or bright background for clear visibility of cross-hairs

What brand of contact lens are made for astigmatism?

Description : What brand of contact lens are made for astigmatism?

Last Answer : Yes, there are indeed contact mafe for people with astigmatism. Acuvue makes a great set of contacts for people with astigmatism.

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.

Cylindrical lens is used by a person suffering from - (1) astigmatism (2) myopia (3) hypermetropia (4) None of these

Description : Cylindrical lens is used by a person suffering from - (1) astigmatism (2) myopia (3) hypermetropia (4) None of these

Last Answer : (1) astigmatism Explanation: A cylindrical lens is typically used to focus, condense or expand incoming light. A cylindrical lens has one cylindrical surface, causing light to be focused in a single dimension or axis.

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.

In reciprocal levelling, the error which is not completely eliminated, is due to (A) Earth's curvature (B) Non-adjustment of line of collimation (C) Refraction (D) Non-adjustment of the bubble tube

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Last Answer : (C) Refraction 

Which of the following statements is incorrect? (A) Error due to refraction may not be completely eliminated by reciprocal levelling (B) Tilting levels are commonly used for precision work (C) The last reading of levelling is always a foresight (D) All of the above statements are incorrect

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Last Answer : (D) All of the above statements are incorrect

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

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Last Answer : (D) All the above 

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

The most serious manufacturing defect from fracture toughness point of view is (A) Surface roughness (B) Pores (C) Spherical inclusion (D) Crack

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If a drug is eliminated by first order kinetics: A. A constant amount of the drug will be eliminated per unit time B. Its clearance value will remain constant C. Its elimination half life will increase with dose D. It will be completely eliminated from the body in 2 × half life period

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Last Answer : B. Its clearance value will remain constant

If a drug is eliminated by first order kinetics: A. A constant amount of the drug will be eliminated per unit time B. Its clearance value will remain constant C. Its elimination half life will increase with dose D. It will be completely eliminated from the body in 2 × half life period

Description : If a drug is eliminated by first order kinetics: A. A constant amount of the drug will be eliminated per unit time B. Its clearance value will remain constant C. Its elimination half life will increase with dose D. It will be completely eliminated from the body in 2 × half life period

Last Answer : B. Its clearance value will remain constant

Myopia is a defect of Human eye. it can be corrected by using a lens called? A. Convex lens B. Concave lens (Answer) C. Cylindrical lens D. Plano convex lens E. None of these

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ALSO CHECK: Long-sight defect could be corrected by using ----- lens? Deficiency of vitamin B1 is causes-----? A. Rickets B. Bone Infection C. Beriberi (Answer) D. Myopia

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Short-sight defect could be corrected by a ------- lens? A. concave lens (Answer) B. convex lens C. converging lens D. none of these

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ALSO CHECK: Short-sight defect could be corrected by a ------- lens? Deficiency of Vitamin-A results in -----? A. Night blindness (Answer) B. rickets C. scurvy D. hair fall

Description : ALSO CHECK: Short-sight defect could be corrected by a ------- lens? Deficiency of Vitamin-A results in -----? A. Night blindness (Answer) B. rickets C. scurvy D. hair fall

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What was a short term effect of James Bradley's discovery of aberration of light?

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Description : 4. A spherical mirror and a thin spherical lens have a focal length of -15 cm. The mirror and the lens are likely to be -Physics-10

Last Answer : (a) Both are likely to be concave.

With respect to lens development: a. the lens first appears at 27 days of gestation b. it is formed from neural crest cells c. the lens first appears as a vesicles with a single layer of epithelial cells d. Y suture is absent in the embryonic nucleus e. the adult lens is more spherical than the foetal

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What type of lens decelerates a portion of a spherical wavefront

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How does a waveguide-type lens focus spherical wavefront microwave energy?

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Find the amount of water displaced by a solid spherical ball of diameter 4.2 cm, when it is completely immersed in water. -Maths 9th

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Pick out the correct statement. (A) Higher is the temperature of the radiating body, higher is the wavelength of radiation (B) Logarithmic mean area is used for calculating the heat flow rate through a thick walled cylinder (C) The wavelength corresponding to maximum mono-chromatic emissive power increases with rise in temperature (D) Solid angle subtended by the finite surface at the radiating element is called the angle of incidence

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