Q.1
The unit of magnetic flux is the
  • Henry
  • Tesla
  • Faraday
  • Weber
Q.2
Resolving power of a telescope is
  • 1.22λ2a\frac{1.22λ}{2a}2a1.22λ​
  • 2a1.22 λ\frac{2a}{1.22\ \lambda}1.22 λ2a​
  • (2nsin⁡β)1.22λ\frac{\left(2n\sin\beta\right)}{1.22\lambda}1.22λ(2nsinβ)​
  • 1.22λ2n sin⁡β\frac{1.22\lambda}{2n\ \sin\beta}2n sinβ1.22λ​
Q.3
Two light sources are coherent when:
  • their amplitudes are same
  • their frequencies are same
  • their wavelengths are same
  • their frequencies are equal and their phase difference is constant
Q.4
In young's double slit experiment
  • all fringes have same thickness
  • central bright is of double width
  • central fringe is intense
  • thickness of fringes decreases gradually
Q.5
Resolving power of microscope depends upon
  • (a) wavelength of light used (directly proportional)
  • b) wavelength of light used (inversely proportional)
  • (c) frequency of light used
  • d) focal length of objective
Q.6
Surrounding every moving electron is
  • (a) a magnetic field
  • (b) an electric field
  • (c) both of these
  • (d) none of these
Q.7
If a wave from one slit of a Young's double-slit experiment set-up arrives at a point on the screen one wavelength behind the wave from the other slit, what is observed at that point?
  • dark fringe
  • bright fringe
  • multi-colored fringe
  • gray fringe, neither bright nor dark
Q.8
Two coherent sources of light can be obtained from
  • Two different lamps
  • Two different lamps but of the same colour
  • Two different lamps of the same colour and having the same colour
  • None of these
Q.9
Resolving power of a microscope is
  • 1.22λ2a\frac{1.22λ}{2a}2a1.22λ​
  • 2a1.22 λ\frac{2a}{1.22\ \lambda}1.22 λ2a​
  • (2nsin⁡β)1.22λ\frac{\left(2n\sin\beta\right)}{1.22\lambda}1.22λ(2nsinβ)​
  • 1.22λ2n sin⁡β\frac{1.22\lambda}{2n\ \sin\beta}2n sinβ1.22λ​
Q.10
Coherent sources have
  • same frequency
  • constant or zero phase difference
  • both a and b
  • none of these
Q.11
In the young's double slit experiment, if monochromatic light is replaced by white light , then
  • no fringes are observed
  • all bright fringes become white
  • all bright fringes have colours between violet and red
  • only central fringe is white and all other fringes are coloured
Q.12
The fringe width in YDS expt on a screen which is placed at a distance offrom the slits 10-apart when light used has wavelength 6 X 10-7 m , is equal to :
  • 3 X 10-10 m
  • 3 X 10-4 m
  • 6 X 10-10 m
  • 6 X 10-4 m
Q.13
If the ratio of amplitudes of two interfering waves is 4 : 3 , then the ratio of maximum and minimum intensity is :
  • 16 : 18
  • 18 : 16
  • 49 : 1
  • 94 : 1
Q.14
In YDS expt , the intensity on the screen at a point where path difference is λ is K. what will be the intensity at the point where path difference is ( λ /4)
  • K / 4
  • K / 2
  • K
  • zero
Q.15
The phenomenon of diffraction can be exhibited by :
  • Infrared waves
  • microwaves
  • X - rays
  • all of these
Q.16
Light of wavelength 2 X 10-3 m falls on a slit of width 4 X 10-3 m. The angular dispersion of the central maximum will be :
  • 300
  • 600
  • 900
  • 1800
Q.17
Waves that cannot be polarised are:
  • light waves
  • electromagnetic waves
  • transverse waves
  • longitudinal waves
Q.18
Two polaroids are kept crossed to each other. Now one of them is rotated through an angle ofThe percentage of incident light now transmitted through the system is:
  • 15 %
  • 25 %
  • 50 %
  • 60 %
Q.19
The fringe width of bands in YDS expt can be increased by:
  • decreasing the wavelength of light used.
  • decreasing the distance between the two sources
  • increasing the distance between the two sources
  • dipping the apparatus into water
Q.20
The dual nature of light is exhibited?
  • diffraction and photoelectric effect
  • photoelectric effect
  • refraction & interference
  • diffraction & reflection
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