Title 10. WAVE OPTICS(H).pdf ✅

NEET REVISION wavelength of red light is , then wave‐ length of first maximum will be [Q367688] (1) (2) (3) (4) 11. A Fresnel biprism of angle is illuminated by light of wavelength from a source which is away from it. What will be the width of the fringes formed on a screen kept away from the biprism? (Take Refractive index of glass ) [Q367971] (1) (2) (3) (4) 12. Figure shows a double slit experiment, and are the two coherent sources. The path lengths and are and respectively where is whole number and is wavelength. Taking the central bright fringe has zero path dif‐ ference, what is formed at ? [Q368058] (1) First Bright (2) First Dark (3) Fourth Bright (4) Second Dark 13. When a mica sheet of thickness 7 microns and is placed in the path of one of interfer‐ ing beams in the biprism experiment then the central fringe gets at the position of seventh bright fringe. The wavelength of light used will be [Q367994] (1) (2) (3) (4) 14. Using monochromatic light of wavelength , an experimentalist sets up the Young's double slit experiment in three ways as shown. If she ob‐ serves that , the wavelength of light used is [Q367999] (1) (2) (3) (4) 15. A monochromatic light source of wavelength is placed at . Three slits and are equidistant from the source and the point on the screen. and . If be the intensity at when only one slit is open, the intensity at when all the three slits are open is [Q367791] (1) 31 (2) 51 (3) 81 (4) Zero 16. A line emitted by hydrogen in a star is observed to be red shifted by . Find the speed with which star is receding away from the earth. [Q367741] (1) (2) (3) (4) 17. In young's double slit experiment, the two slits are ' ' distance apart. Interference pattern is ob‐ served on the screen at a distance ' ' from the slits. First dark fringe is observed on the screen directly opposite to one of the slits. The wave‐ length of the light is [Q368091] 6000 ∘ A 5500 ∘ A 3300 ∘ A 6600 ∘ A 4400 ∘ A 2 ∘ 6280A ∘ 0.10 m 0.9 m = 1.5, π = 3.14 0.35 mm 0.18 mm 0.12 cm 0.25 cm P Q PY QY nλ (n + 4)λ n λ Y μ = 1.6 4000 A ∘ 5000 A ∘ 6000 A ∘ 7000 A ∘ λ y = β 580nm 560nm 520nm 540nm λ S S1 , S2 S3 S P S1P − S2P = λ/6 S1P − S3P = 2λ/3 I P S3 P 6000 o A Hβ 10 o A 5 × 10 5m/s 10 5m/s 100m/s 5 × 10 3m/s d D

NEET REVISION 28. In young's double slit experiment, the phase dif‐ ference between the light waves reaching a point where third bright fringe forms will be [Q368025] (1) Zero (2) (3) (4) 29. A monochromatic light of wavelength is incident on the single slit of width If the diffraction pattern is formed at the focus of the convex lens of focal length the linear width of the central maximum is _____ . [Q367714] (1) (2) (3) (4) 30. A light of wavelength is incident on a Young's double slit. The distance between slit and screen is and distance between slits is . If screen moves with a speed of , then with what speed first maxima will move? [Q368017] (1) (2) (3) (4) 31. In Young's double slit experiment, the interfer‐ ence pattern is found to have an intensity ratio between bright and dark fringes as 16. Then the ratio of their amplitudes will be [Q368071] (1) 1.67 (2) 3.24 (3) 5.79 (4) 2.26 32. In Young's double slit experiment, an electron beam is used to produce interference fringes of width . Now the electron beam is replaced by a beam of protons with the same experimental set-up and same speed. The fringe width ob‐ tained is . The correct relation between and is [Q368055] (1) (2) No fringes are formed (3) (4) 33. In Young’s double slit experiment using monochromatic light of wavelength , the inten‐ sity of light at a point on the screen with path difference is unit. The intensity of light at a point where path difference is is [Q368034] (1) (2) (3) (4) 34. If white light is used in the Newton's rings ex‐ periment, the colour observed in the reflected light is complementary to that observed in the transmitted light through the same point. This is due to [Q367985] (1) change of phase in one of the reflected waves (2) change of phase in one of the reflected waves (3) change of phase in one of the reflected waves (4) change of phase in one of the reflected waves 35. In Young's double slit experiment, the position of bright fringe from the central maximum is . The distance between slit and screen is and wavelength of used monochromatic light is . The separation between the slits is [Q368116] (1) (2) (3) (4) 36. Light of wavelength falls normally on a slit of width . The angular po‐ sition of the second minima from the central maximum will be (in radians): [Q367732] (1) (2) (3) (4) 37. The young's double slit experiment is per‐ formed with light of wavelength where in 16 fringes occupy a certain region on the screen. If 24 fringes occupy the same region with an‐ other light of wavelength , then is: [Q368050] (1) (2) (3) (4) 38. The highest order of spectrum which may be seen with monochromatic light of wavelength 6000 by using a grating with 5000 lines/ is [Q367822] (1) 1 (2) 2 (3) 3 (4) 6 39. If the ratio of the intensity of two coherent sources is 4 then the visibility of the fringes is [Q367802] (1) 4 (2) (3) (4) 9 40. A single slit of width is illuminated by a co‐ herent monochromatic light of wavelength . If the second and fourth minima in the difdfraction pattern at distance from the slit are at and respectively from the central maximum (λ = 6000 ∘ A) 2π 4π 6π 6000A ∘ 0.01 mm. 20 cm, 120 mm 12 mm 60 mm 24 mm 500 nm D = 1.8 m d = 0.4 mm 4 ms −1 5 mms −1 4 mms −1 3 mms −1 2 mms −1 β1 β2 β1 β2 β1 = β2 β1 < β2 β1 > β2 λ λ M λ/3 M 8 M 16 M 4 M 2 90 ∘ 180 ∘ 145 ∘ 45 ∘ 5 th 5m 1m 600nm 36μm 60μm 12μm 48μm 550 nm 22.0 × 10 −5 cm π 4 π 8 π 12 π 6 6000 ∘ A λ λ 6000 ∘ A 4500 ∘ A 5000 ∘ A 4000 ∘ A A ∘ cm [(Imax − Imin ) / (Imax + Imin )] 4/5 3/5 b λ 1 m 3 cm 6 cm