The intermediate image formed by the objective of a compound microscope is
Options
(a) real, inverted and magnified (b) real, erect and magnified (c) virtual, erect and magnified (d) virtual, inverted and magnified
Correct […]
Astigmatism is corrected by using
Options
(a) cylindrical lens (b) plano-convex lens (c) plano-concave lens (d) convex lens
Correct Answer:
cylindrical lens
Explanation:
In this defect, eye cannot perpendicular directions clearly that is horizontal […]
A focal length of a lens is 10 cm. What is power of a lens in dioptre?
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(a) 0.1 D (b) 10 D (c) 15 D (d) 1 D
Correct Answer:
10 […]
A luminous object is seperated from a screen by distance d. A convex lens is placed between the object and the screen such that it forms a distinct image on the screen. The maximum possible […]
Two lenses of power 15 D and -3 D are placed in contact. The focal length of the combinations is
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(a) 10 cm (b) 15 cm (c) 12 cm (d) 8.33 cm
The equiconvex lens has focal length f. If it is cut perpendicular to the principal axis passing through optical centre, then focal length of each half is
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(a) f/2 (b) f (c) 3f/2 […]
In vacuum, to travel distance d, light takes time t and in medium to travel distance 5d, it takes time T. The critical angle of the medium is
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(a) sin⁻¹(5T/t) (b) sin⁻¹(5t/3T) (c) […]
An object placed at 20 cm in front of a concave mirror produces three times magnified real image. What is the focal length of the concave mirror?
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(a) 15 cm (b) 6.6 cm […]
To get three images of single object, one should have two plane mirrors at an angle of
Options
(a) 60⁰ (b) 90⁰ (c) 120⁰ (d) 30⁰
Correct Answer:
90⁰
Explanation:
Consider the diagram where […]
To measure the roughness of the surface of a material, which of the following microscope is preferred for better result output?
Options
(a) Compound microscope (b) Electron microscope (c) Atomic force microscope (d) […]
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