Wave-Optics-Quiz-5

Wave Optics Quiz-5

Dear Readers,

As per analysis for previous years, it has been observed that students preparing for NEET find Physics out of all the sections to be complex to handle and the majority of them are not able to comprehend the reason behind it. This problem arises especially because these aspirants appearing for the examination are more inclined to have a keen interest in Biology due to their medical background. 

Furthermore, sections such as Physics are dominantly based on theories, laws, numerical in comparison to a section of Biology which is more of fact-based, life sciences, and includes substantial explanations. By using the table given below, you easily and directly access to the topics and respective links of MCQs. Moreover, to make learning smooth and efficient, all the questions come with their supportive solutions to make utilization of time even more productive. Students will be covered for all their studies as the topics are available from basics to even the most advanced. 

Q41. In Young’s double slit experiment distance between source is 1 mm and distance between the screen and source is 1m.If the fringe width on the screen is0.06 cm, then λ is

•  6000 Å
•  4000 Å
•  1200 Å
•  2400 Å

Solution

Q42. In an interference experiment, third bright fringe is obtained at a point on the screen with a light of 700 nm. What should be the wavelength of the light source in order to obtain 5th bright fringe at the same point?

•  500 nm
•  630 nm
•  750 nm
•  420 nm

Solution
n₁ λ₁=n₂ λ₂

⇒3×700=5×λ₂ 

 ⇒ λ₂=420 nm

Q43.Light passes successively through two polarimeter tubes each of length 0.29m. The first tube contains dextro rotatory solution of concentration 60kgm^-3 and specific rotation 0.01rad m² kg^-1. The second tube contains laevo rotatory solution of concentration 30kg/m³ and specific rotation 0.02radm² kg^-1. The net rotation produced is

•  15°
•  0°
•  20°
•  10°

Solution
Rotation produced θ=Sic Net rotation produced θ_r=θ₁-θ₂=l(S₁ c₁-S₂ c₂) 

 =0.29×[0.01×60-0.02×30]=0

Q44. For the sustained interference of light, the necessary condition is that the two sources should

•  Have constant phase difference
•  Be narrow
•  Be close to each other
•  Of same amplitude

Solution
The essential condition for sustained interference is constancy of phase difference

Q45.The electromagnetic waves travel with a velocity

•  Equal to velocity of sound
•  Equal to velocity of ligh
•  Less than velocity of light
•  None of these

Solution

Q46.A parallel monochromatic beam of light is incident normally on a narrow slit.A diffraction pattern is formed on a screen placed perpendicular to the direction of incident beam.At the first maximum of the diffraction pattern, the phase difference between the rays coming from the edges of the slit is

•  0
• π/2
•  π
•  2π

Solution
2π

Q47.A light source approaches the observer with velocity 0.8 c. The Doppler shift for the light of wavelength 5500Å is

•  4400 Å
•  1833 Å
•  3167 Å
•  7333 Å

Solution

                    

Q48.A parallel beam of monochromatic light of wavelength 5000 Å is incident normally on a single narrow slit of width 0.001mm.The light is focused by a convex lens on a screen placed on the focal plane. The first minimum will be formed for the angle of diffraction equal to

•  0°
•  15°
•  30°
•  60°

Solution

 

Q49.In a Young’s experiment, two coherent sources are placed 0.90 mm apart and the fringes are observed one metre away.If it produces the second dark fringe at a distance of 1 mm from the central fringe, the wavelength of monochromatic light used would be

•  60×10^-4 cm
•  10×10^-4 cm
•  10×10^-5 cm
•  6×10^-5 cm

Solution
                      

Q50. For what distance is ray optics a good approximation when the aperture is 4mm wide and the wavelength is 500 nm

•  32 m
•  64 m
•  16 m
•  8 m

Solution