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Set 7 of 10 · Questions 181-210 of 295

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JEE Main Physics · Wave Optics · Set 7 (Q181-210)

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  1. 181.
    If numerical aperture of a microscope is increased, then its
    1. (1)resolving power remains constant.
    2. (2)resolving power becomes zero.
    3. (3)limit of resolution is decreased.
    4. (4)limit of resolution is increased.
  2. 182.
    In Young's double slit experiment, light from two identical sources are superimposing on a screen. The path difference between the two lights reaching at a point on the screen is . The ratio of intensity of fringe at this point with respect to the maximum intensity of the fringe is :
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  3. 183.
    What would be the angular separation between the consecutive bright fringes in Young's double slit experiment with blue-green light of wavelength 400 ? The separation between the slits is .
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  4. 184.
    In free space, an electromagnetic wave of 3 GHz of 3 GHz frequency strikes over the edge of an object of size , where is the wavelength of the wave in free space. The phenomenon, which happens there will be:
    1. (1)Reflection
    2. (2)Refraction
    3. (3)Diffraction
    4. (4)Scattering
  5. 185.
    In a Young’s double slit experiment, the two slits act as coherent sources of waves of equal amplitude A and wavelength λ. In another experiment with the same arrangement the two slits are made to act as incoherent sources of waves of same amplitude and wavelength. If the intensity at the middle point of the screen in the first case is and in the second case is , then the ratio is :
    1. (1)2
    2. (2)1
    3. (3)0.5
    4. (4)4
  6. 186.
    Light from two coherent sources of the same amplitude and wavelength illuminates the screen. The intensity of the central maximum is . If the sources were incoherent, the intensity at the same point will be
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  7. 187.
    If the slit width is and wavelength of light used is , then Fresnel distance is nearly
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  8. 188.
    In an interference experiment the ratio of amplitudes of coherent waves is Theratio of maximum and minimum intensities of fringes will be:
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  9. 189.
    The distance of a point on the screen from two slits in biprism experiment is and . If wavelength of light used is , the fringe formed at that point is
    1. (1)  bright
    2. (2)  dark
    3. (3)  bright
    4. (4)  dark
  10. 190.
    In Young's double slit experiment, two wavelengths and are used to obtain interference fringes. If the bright band due to coincides with bright band due to , then the value of is
    1. (1)4
    2. (2)3
    3. (3)2
    4. (4)6
  11. 191.
    The polarizing angle of glass is . A ray of light which is incident at this angle will have an angle of refraction as
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  12. 192.
    When a light ray incidents on the surface of a medium, the reflected ray is completely polarized. Then the angle between reflected and refracted rays is
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  13. 193.
    In Young’s double slits experiment, the position of bright fringe from the central maximum is 5 cm. The distance between slits and screen is 1 m and wavelength of used monochromatic light is 600 nm. The separation between the slits is:
    1. (1)60m
    2. (2)48m
    3. (3)12 m
    4. (4)36 m
  14. 194.
    Which of the following phenomena can not be explained by wave theory of light?
    1. (1)Compton effect
    2. (2)Refraction of light
    3. (3)Reflection of light
    4. (4)Diffraction of light
  15. 195.
    Two light waves of intensities ' ' and ' ' having same frequency pass through same medium at a time in same direction and interfere. The sum of the minimum and maximum intensities is
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  16. 196.
    Two coherent light sources having intensity in the ratio produce an interference pattern. Then the value of will be
    1. (1)
    2. (2).
    3. (3)
    4. (4)
  17. 197.
    Given below are two statements:
    Statement I: A plane wave after passing through prism remains as plane wave but passing through small pin hole may become spherical wave.
    Statement II: The curvature of a spherical wave emerging from a slit will increase for increasing slit width.
    In the light of the above statements, choose the correct answer from the options given below
    1. (1)Both Statement I and Statement II are true
    2. (2)Statement I is false but Statement II is true
    3. (3)Both Statement I and Statement II are false
    4. (4)Statement I is true but Statement II is false
  18. 198.
    In a single slit experiment, the width of the slit is doubled. Which one of the following statements is correct?
    1. (1)The intensity and angular width of the central maximum are unaffected.
    2. (2)The intensity remains same and angular width becomes half.
    3. (3)The intensity and angular width both are doubled.
    4. (4)The intensity increases by a factor 4 and the angular width decreases by a factor of .
  19. 199.
    Using the expression 2d sin θ = λ, one calculates the values of d by measuring the corresponding angles θ in the range 0 to 90º. The wavelength λ is exactly knowns and the error in θ is constant for all values of θ. As θ increases from 0º :
    1. (1)the absolute error in d remains constant.
    2. (2)the absolute error in d increases.
    3. (3)the fractional error in d remains constant.
    4. (4)the fractional error in d decreases
  20. 200.
    Which of the statements are correct with reference to single slit diffraction pattern?
    (i) Fringes are of unequal width
    (ii) Fringes are of equal width
    (iii) Light energy is conserved
    (iv) Intensities of all bright fringes are equal
    1. (1)(i) and (iii)
    2. (2)(i) and (iv)
    3. (3)(ii) and (iv)
    4. (4)(ii) and (iii)
  21. 201.
    A single slit of width a is illuminated by a monochromatic light of wavelength 600 nm. The value of a for which first minimum appears at = 30° on the screen will be :
    1. (1)1.2m
    2. (2)3m
    3. (3)1.8m
    4. (4)0.6m
  22. 202.
    Statement - 1 : On viewing the clear blue portion of the sky through a Calcite Crystal, the intensity of transmitted light varies as the crystal is rotated.
    Statement – 2 :The light coming from the sky is polarized due to scattering of sun light by particles in the atmosphere. The scattering is largest for blue light
    1. (1)Statement-1 is true, statement-2 is false.
    2. (2)Statement-1 is true, statement-2 is true, statement-2 is the correct explanation of statment-1
    3. (3)Statement-1 is true, statement-2 is true, statement-2 is not the correct explanation of statement-1
    4. (4)Statement-1 is false, statement-2 is true.
  23. 203.
    Two coherent sources and produce interference at point on the screen where there is a dark band which is formed between bright band and bright band. Wavelength of light used is . The path difference between and is
    1. (1)
    2. (2)
    3. (3)
    4. (4)
  24. 204.
    In a Young's double slit experiment, two slits are located 1.5 mm apart. The distance of screen from slits is 2 m and the wavelength of the source is 400 nm. If the 20 maxima of the double slit pattern are contained within the central maximum of the single slit diffraction pattern, then the width of each slit is , where -value is_____.
  25. 205.
    In a Young's double slit experiment set up, the two slits are kept 0.4 mm apart and screen is placed at 1 m from slits. If a thin transparent sheet of thickness is introduced in front of one of the slits then center bright fringe shifts by 20 mm on the screen. The refractive index of transparent sheet is given by , where is
  26. 206.
    The ratio of the power of a light source to that the light source is is emitting photons per second at 600 nm.If the wavelength of the source is 300 nm, then the number of photons per second emitted by is .
  27. 207.
    White light is passed through a double slit and interference is observed on a screen 1.5m away. The separation between the slits is 0.3mm. The first violet and red fringes are formed 2.0mm and 3.5mm away from the central white fringes. The difference in wavelengths of red and voilet light is .......nm
  28. 208.
    In a single slit diffraction pattern, a light of wavelength is used. The distance between the first and third minima in the diffraction pattern is found to be when the screen in placed away from slits. Thewidth of the slit is____ .
  29. 209.
    The electric field in an electromagnetic wave is given by .
    The energy contained in a cylinder of volume V is . The value of V is given )
  30. 210.
    Two beams of light having intensities I and 4I interfere to produce a fringe pattern on a screen. The phase difference between the two beams are /2 and /3 at points A and B respectively. The difference between the resultant intensities at the two points is xI. The value of x will be_____.