Tiêu đề 09. RAY OPTICS AND OPTICAL INSTRUMENTS(H).pdf ✅

NEET REVISION 09. RAY OPTICS AND OPTICAL INSTRUMENTS(H) NEET REVISION Date: March 18, 2025 Dura on: 1:00:00 Total Marks: 180 INSTRUCTIONS INSTRUCTIONS PHYSICS 1. A concave mirror of radius is kept on a hori‐ zontal table (figure). Water (refractive index ) is poured into it upto a height . What should be the distance of a point object from surface along principal axis so that its final image is formed on itself. Consider two cases. [Q364905] (1) (2) (3) (4) 2. A convex lens makes a real image long on a screen. When the lens is shifted to a new posi‐ tion without disturbing the object, we again get a real image on screen which is tall. The length of the object must be: [Q364817] (1) (2) (3) (4) 3. A small telescope has an objective lens of focal length and eye piece of focal length . The telescope is used to view a tall tower away. The height of the image of the tower formed by objective lens is [Q364543] (1) (2) (3) (4) 4. If an observer is walking away from the plane mirror with . Then the velocity of the image with respect to observer will be [Q364641] (1) (2) (3) (4) 5. The power of a thin convex lens is When it is placed in a liquid of refractive index , then it behaves as a concave lens of focal length . The refractive index of the liquid will be [Q364796] (1) (2) (3) (4) 6. For the thin convex lens, the radii of curvature are at and respectively. The focal length of the lens is The refractive index of the material is [Q364851] (1) 1.4 (2) 1.2 (3) 1.8 (4) 1.5 7. The plane face of a plano-convex lens is silvered. If be the refractive index and be the radius of curvature of curved surface, then system will behave like a concave mirror of curvature [Q364890] (1) (2) (3) (4) 8. An unnumbered wall clock shows time : 37 , where term represents hours, repre‐ sents minutes and the last term represents sec‐ onds. What time will its image in a plane mirror show. [Q364680] (1) (2) (3) (4) None of these 9. A thin prism of angle , are made from a glass of refractive index 1.54, is combined with another thin prism made from a glass of re‐ fractive index 1.72 , to produce dispersion with‐ out deviation. The angle of is: [Q365094] (1) (2) R = μ h (R − h)μ ( ) R−h μ h μ R μ 4 cm 16 cm 1/4 cm 8 cm 12 cm 20 cm 140 cm 5.0 cm 100 m 3 km cm 14 3 cm 11 3 cm 17 3 cm 8 3 6 m/ sec 10 m/ sec 12 m/ sec 24 m/ sec 6 m/ sec (ang = 1.5) 5.0D. anl 100 cm anl 5/3 4/3 √3 5/4 15 cm 30 cm 20 cm. μ R μR R 2/μ R/(μ − 1) [(μ + 1)/(μ − 1)]R 04 : 25 1 st 2 nd 08 : 35 : 23 07 : 35 : 23 07 : 34 : 23 P1 4 ∘ P2 P2 5.33 ∘ 4 ∘

NEET REVISION 21. Find focal length and nature of silvered equiconvex lens of radius of curvature & refractive index 2 placed in a medium of refrac‐ tive index 3. [Q364883] (1) , silvered lens will be like a convex mirror (2) , silvered lens will be like a concave mirror (3) , silvered lens will be like a convex mirror (4) , silvered lens will be like a convex mirror 22. A cube of side is placed in front of a con‐ cave mirror of focal length with its face at a distance of and face at a distance of from the mirror. The distance between the image of face and is [Q364722] (1) (2) (3) (4) 23. An astronomical telescope has objective and eyepiece of focal length and respec‐ tively. To view an object away from the objective, the lenses must be separated by a dis‐ tance [Q364552] (1) (2) (3) (4) 24. A plane mirror is place along the -axis facing negative -axis. The mirror is fixed. A point ob‐ ject is moving with velocity in front of plane mirror. The relative velocity of image with respect of its object [Q364642] (1) (2) (3) (4) 25. A small telescope has an objective of focal length and an eye piece of focal length . The magnifying power of telescope for viewing a distant object is: [Q364570] (1) 34 (2) 28 (3) 17 (4) 32 26. Given, and . There is an equiconvex lens with radius of each surface equal to . There is air in the object space and water in the image space. The focal length of lens is [Q364867] (1) (2) (3) (4) 27. Critical angle of incidence for a pair of optical media is . The refractive indices of first and second media are in the ratio [Q364958] (1) (2) (3) (4) 28. A square wire of side is placed away from a concave mirror of focal length as shown in the figure (not to the scale). What is the area enclosed by the image of the wire in ? [Q364704] (1) 1.44 (2) 3.26 (3) 5.47 (4) 2.94 29. A fish looking up through the water sees the outside world contained in a circular horizon. If the redfractive index of water is and the fish is . below the surface, the radius of this circle in is [Q364939] (1) (2) (3) (4) 30. A layer of benzene deep floats on water deep. When viewed vertically through air, the apparent distance of the bottom of the vessel below the free surface of benzene is [Q364914] (1) (2) (3) (4) 31. A plastic hemisphere has a radius of curvature of and an index of refraction of 1.6. On the axis halfway between the plane surface and the spherical one ( from each) is a small object . The distance between the two images when viewed along the axis from the two sides of the hemisphere is approximately [Q364799] (1) (2) (3) (4) 32. A man of height wishes to see his full image in a plane mirror placed at a distance of 20 cm 30 cm 30 cm 20 cm 0 cm 2 m 1 m P 3 m Q 5 m P Q 0.5 m 1 m 0.25 m 0.5 m 50 m 10 m 250 m 72.5 cm 54.1 cm 91.4 cm 48.2 cm x y 2^i + 4^j 8j −8j −6i 3i − 4j 140 cm 5.0 cm aμg = 3 2 aμw = 4 3 20 cm 80 cm 40 cm 20 cm 10 cm 45 ∘ 1 : 2 1 : √2 √2 : 1 2 : 1 4.8 cm 90 cm 18 cm cm2 4/3 12 cm cm 4√5 36√5 36√7 36/√7 (μ = 1.5)6 cm (μ = ) , 4 cm 4 3 14 cm 7 cm 21 cm 3.5 cm 8 cm 4 cm O 2.5 cm 6 cm 4 cm 2 cm 1.6 m
NEET REVISION . The minimum length of the mirror should be [Q364674] (1) (2) (3) (4) 33. An equiconvex lens made of glass of refractive index has focal length in air. It is com‐ pletely immersed in water of refractive index . The percentage change in the focal length is [Q364868] (1) decrease (2) increase (3) increase (4) decrease 34. When an object is at a distance and from the optical centre of a lens, a real and a virtual image are formed, respectively with same mag‐ nification. The focal length of lens is [Q364829] (1) (2) (3) (4) 35. The effective focal length of the lens combina‐ tion shown in the figure is . The radii of curvature of the curved surfaces of the plano - convex lenses are each and refractive in‐ dex of the material of the lens is 1.5 . What would be the refractive index of the liquid? [Q364763] (1) 1.33 (2) 1.42 (3) 1.53 (4) 1.6 36. A person has been using spectacles of power -1.0 dioptre for distant vision and a separate reading glass of power 2.0 dioptres. What is the least distance of distinct vision for this person? [Q364596] (1) (2) (3) (4) 37. The ratio of angle of minimum deviation of a prism in air and when dipped in water will be and if prism angle is very small. [Q365062] (1) (2) (3) (4) 4 38. In the figure shown here, what is the equivalent focal length of the combination of lenses (Assume that all layers are thin)? [Q364772] (1) (2) (3) (4) 39. One of the refracting surface of a prism is sil‐ vered. A ray of light incident at an angle re‐ traces its path. If the refractive index of the mate‐ rial of prism is , the angle of prism will be [Q365120] (1) (2) (3) (4) 40. If the focal lengths of objective and eye lens of a microscope are and respectively and the object is put away from the ob‐ jective lens and the final image is formed at in‐ finity, then magnifying power of the microscope is [Q364631] (1) 150 (2) 200 (3) 250 (4) 400 41. A plane mirror is placed at a distance of in front of a concave mirror of focal length . A short object is to be placed between the mirrors and facing both the mirrors so that its virtual image in the plane mirror coincides with the real image in concave mirror. What should be the distance of the object from the plane mirror? [Q364886] (1) (2) (3) (4) 42. The image of point when viewed from top of two identical slabs having thickness will be : [Q364916] (1) above (2) above (3) above (4) below 43. Find the position of final image from first lens. Given, focal length of each lens is 2 m 0.4 m 0.8 m 1.6 m 2.4 m 3 2 f 4 3 4000% 300% 400% 300% x y x + y (x + y)/2 x + y/2 √xy −60 cm 12 cm 10 cm 40 cm 30 cm 50 cm (aμg = 3/2 aμw = 4/3) 1/8 1/2 3/4 −40 cm −100 cm −50 cm 40 cm 60 ∘ √3 30 ∘ 45 ∘ 53 ∘ 60 ∘ 1.2 cm 3 cm 1.25 cm 50 cm 16 cm 15 cm 30 cm 40 cm 20 cm P 2 cm 1.5 cm P 2.0 cm P 1.33 cm P 2.9 cm P 10 cm.