NEET Physics Diffraction Polarisation of Light and Resolving Power MCQs

a) sharper and brighter

b) broader adn fainter

c) broader and brighter

d) sharper and fainter

Answer: sharper and brighter

Question: When monochromatic light is replaced by white light in Fresnel’s biprism arrangement, the central fringe is

a) white

b) None of these

c) coloured

d) dark

Answer: white

Question: Light transmitted by nicol prism is

a) plane polarised

b) elliptically polarised

c) circularly polarised

d) unpolarised

Answer: plane polarised

Question: Optically active substances are those substances which

a) rotate the plane of polarisation of polarised light

b) produces double refraction

c) produces polarised light

d) converts a plane polarised light into circularly polarised light.

Answer: rotate the plane of polarisation of polarised light

Question: The condition for observing Fraunhoffer diffraction from a single slit is that the light wavefront incident on the slit should be

a) plane

b) spherical

c) cylindrical

d) elliptical

Answer: plane

Question: When ordinary light is made incident on a quarter wave plate, the emergent light is

a) elliptically polarised

b) circulary polarised

c) unpolarised

d) linearly polarised

Answer: elliptically polarised

Question: In the propagation of light waves, the angle between the plane of vibration and plane of polarisaiton is

a) 90º

b) 45º

c) 80º

d) None of these

Answer: 90º

More Questions.....................................................

Question: The phenomenon of diffraction can be treated as interference phenomenon if the number of coherent sources is

a) infinity

b) zero

c) two

d) one

Answer: infinity

Question: From Brewster’s law of polarisation, it follows that the anlge of polarisaiton depends upon

a) the wavelength of light

b) plane of polarisation’s orientation

c) plane of vibration’s orientation

d) None of these

Answer: the wavelength of light

Question:

a) 1.3 micron

b) 3250 Å

c) Both

d) None of these

Answer: 1.3 micron

Question: The angle of incidence at which reflected light is totally polarized for reflection from air to glass (refractive index n), is

a) tan^–1(n)

b) sin^–1(1/n)

c) Both

d) None of these

Answer: tan^–1(n)

Question: The diffraction effects in a microscopic specimen become important when the separation between two points is

a) comparable to the wavelength of light used

b) independent of the wavelength of light used.

c) much less than the wavelength of light used.

d) much greater than the wavelength of light used

Answer:  comparable to the wavelength of light used

Question: When unpolarised light is incident on a plane glass plate at Brewster’s angle, then which of the following statements is correct?

a) Reflected light is plane polarised but transmitted light is partially polarised

b) Reflected light is partially polarised but refracted light is plane polarised

c) Reflected and refracted rays are completely polarised with their planes of polarization perpendicular to each other

d) None of these

Answer: Reflected light is plane polarised but transmitted light is partially polarised

Question: The angle substanded by the first diffraction minimum for a point source viewed in the hydrogen line at 1420 MHz with a radio telescope having an aperture of 25 m is

a) 1.2°

b) 2.2°

c) 0.64°

d) 0.8°

Answer: 1.2°

Question: An unpolarised beam of intensity 2a² passes through a thin polaroid. Assuming zero absorption in the polaroid, the intensity of emergent plane polarised light will be

a) a²

b) 2a²

c)

d) None of these

Answer:  a²