Q.1
Which of the following spherical lenses does not exhibit dispersion? The radii of curvature of the surface of the lenses are as given in the diagram [ IIT 2002]
  • a)
    ch-11_qn-80choice_img_no1.png
  • b)
    ch-11_qn-80choice_img_no2.png
  • c)
    ch-11_qn-80choice_img_no3.png
  • d)
    ch-11_qn-80choice_img_no4.png
Q.2
In the ideal double slit experiment, when a glass-plate ( refractive index 1.5) of thickness 't' is introduced in the path of one of the interfering beams ( wave-length λ), the intensity at the position where the central maximum occurred previously remains unchanged. the minimum thickness of the glass-plate is [ IIT 2002]
  • a)2λ
  • b) 2λ / 3
  • c)λ / 3
  • d)λ
Q.3
Two plane mirrors A and B are aligned parallel to each other, as shown in figure. A light ray is incident at an angle 30° at a point just inside one end of A. the plane of incidence coincides with the plane of the figure. the maximum number of times the ray undergoes reflections ( including the first one) before it emerges out is [ IIT 2002]
ch-11_que_no-82_img_no1.png
  • a) 28
  • b) 30
  • c)32
  • d)34
Q.4
In the adjacent diagram, CP represents a wavefront and AO and BP, the corresponding two rays. Find the condition on θ for constructive interference at P between the ray BP and reflected ray OP [ IIT 2003]
ch-11_que_no-83_img_no1.png
  • a)cosθ=3λ / 2d
  • b) cosθ=λ / 4d
  • c)secθ - cosθ=λ / d
  • d)secθ - cosθ=4λ / d
Q.5
A ray of light traveling in water is incident on its surface open to air. The angle of incident is i, which is less than the critical angle. Then there will be .. [ IIT 2007]
  • a)only a reflected ray and no refracted ray
  • b) only a refracted ray and no reflected ray
  • c) a reflected ray and refracted ray and the angle between them would be less than 180° - 2i
  • d)a reflected ray and a refracted ray and the angle between them would be greater than 180° -i
Q.6
The size of the image of an object, which is at infinity, as formed by a convex lens of focal length 30cm is 2cm. If a concave lens of focal length 20cm is placed between the convex lens and the image at a distance of 26 cm from the convex lens, calculate the new size of the image [ IIT 2003]
  • a) 1.25 cm
  • b) 2.5 cm
  • c) 1.05 cm
  • d) 2.0 cm
Q.7
A ray of light is incident at the glass-water interface at an angle i, it emerges finally parallel to the surface of water, then the value of ng would be [ IIT 2003]
ch-11_que_no-85_img_no1.png
  • a)(4/3)sin i
  • b) 1 / sini
  • c)4/3
  • d)1
Q.8
A beam of white light is incident on glass air interface from glass to air such that green light just suffers total internal reflection. The colors of the light which will come out to air are [ IIT 2004]
  • a) Violet, Indigo, Blue
  • b) All colors except green
  • c)Yellow, Orange, Red
  • d)White light
Q.9
An equilateral prism is placed on a horizontal surface. A ray PQ is incident onto it. For minimum deviation [ IIT 2004]
ch-11_que_no-87_img_no1.png
  • a) PQ is horizontal
  • b) QR is horizontal
  • c)RS is horizontal
  • d)Any one will be horizontal
Q.10
Monochromatic light of wavelength 400nm and 560nm are incident simultaneously and normally on double slits apparatus whose slits separation is 0.1 mm and screen distance is 1m. Distance between areas of total darkness will be [ IIT 2004]
  • a) 4 mm
  • b) 5.6 mm
  • c) 14 mm
  • d) 28 mm
Q.11
A point object is placed at the centre of glass sphere of radius 6cm and refractive index 1.The distance of virtual image from the surface is [ IIT 2004]
  • a)6 cm
  • b) 4cm
  • c)12cm
  • d)9 cm
Q.12
A convex lens is in contact with concave lens. The magnitude of ratio of their power is 2/Their equivalent focal length is 30 cm. What are their individual focal lengths? [ IIT 2005]
  • a) -15, 10
  • b) -10, 15
  • c)75, 50
  • d)-75, 50
Q.13
A container is filled with water ( n=1.33) upto a height of 33.25 cm. A concave mirror is placed 15cm above the water level and the image of an object placed at the bottom is formed 25 cm below the water level. Focal length of the mirror is [ IIT 2005]
ch-11_que_no-92_img_no1.png
  • a) 15 cm
  • b) 20 cm
  • c) -18.31 cm
  • d) 10 cm
Q.14
Focal length of the plano-convex lens is 15 cm. A small object is placed at A as shown in figure. The plane surface is silvered. The image will be formed at [ IIT 2006]
ch-11_que_no-93_img_no1.png
  • a)60cm to left of the lens
  • b) 12 cm to the left of the lens
  • c)60 cm to right of lens
  • d)30 cm to the left of lens
Q.15
the graph shows relationship between object distance and image distance for equiconvex lens. Then focal length of the lens is [ IIT 2006]
ch-11_que_no-94_img_no1.png
  • a) 0.50±0.05 cm
  • b) 0.50±0.10 cm
  • c)5.00±0.05 cm
  • d)5.00±0.10 cm
Q.16
Rays of light from Sun falls on a biconvex lens of focal length f and the circular image of Sun of radius r is formed on the focal plane of the lens. Then [ IIT 2006]
  • a) Area of image is πr2 and area is directly proportional to f
  • b) Area of image is πr2 and area is directly proportional to f2
  • c)Intensity of image increases if f is increased
  • d)If lower half of the lens is covered with black paper are will become half
Q.17
Two beams of red and violet colors are made to pass separately through a prism ( angle of the prism is 60°). In the position of minimum deviation, the angle of refraction will be [ IIT 2008]
  • a) 30° for both the colors
  • b) greater for violet colors
  • c)greater for red colors
  • d)equal but not 30° for both the colors.
Q.18
A ball is dropped from height of 20 m above the surface of water in a lake. the refractive index of water is 4.A fish inside the tank, in the line of fall of the ball, is looking at the ball. At an instant, when the ball is 12.8 m above the water surface, the fish sees the speed of ball as [ Take g=10 m/s2] [ IIT 2009]
  • a) 9 m/s
  • b) 12 m/s
  • c) 16 m/s
  • d) 21.33 m/s
Q.19
An astronomical telescope has a large aperture to [ IIT 2002]
  • a)reduce spherical aberration
  • b) high resolution
  • c)increase span of observation
  • d)have low dispersion
Q.20
If two mirrors are kept at 60° to each other, then the number of images formed by them is [ AIEEE 2002]
  • a) 5
  • b) 6
  • c)7
  • d)8
Q.21
Electromagnetic waves are transverse in nature is evident by [ AIEEE 2002]
  • a) polarization
  • b) interference
  • c)reflection
  • d)diffraction
Q.22
Wavelength of light used in an optical instrument are λ1=4000 Å and λ2=5000 Å, then ratio of their respective resolving powers ( corresponding toλ1 and λ2) is [ AIEEE 2002]
  • a) 16:25
  • b) 9:1
  • c) 4:5
  • d) 5:4
Q.23
A lens is placed between a source of light and a wall. It forms image of area A1 and A2 on the wall, for its two different positions. The area of the source of light is [ CBSE 1995]
  • a)
    ch-11_qn-105choice_img_no1.png
  • b)
    ch-11_qn-105choice_img_no2.png
  • c)
    ch-11_qn-105choice_img_no3.png
  • d)
    ch-11_qn-105choice_img_no4.png
Q.24
Diameter of plano-convex lens is 6cm and thickness is 3 mm. If speed of light in the material of the lens is 2×108 metres per second, the focal length of the lens is [ CPMT 1989]
  • a) 15 cm
  • b) 20 cm
  • c)30 cm
  • d)10 cm
Q.25
A ray of light falls on the surface of spherical glass paper weight making an angle α with the normal and is refracted in the medium at an angle of β. The angle of deviation of emergent ray from the direction of incident ray from the direction of incident ray is
  • a) (α -β)
  • b)2(α -β)
  • c)(α -β) / 2
  • d)(β - α)
Q.26
Which of the following is used in optical fibers [ AIEEE 2002]
  • a) total internal reflection
  • b) scattering
  • c) diffraction
  • d) refraction
Q.27
Consider telecommunication through optical fibers. Which of the following statement is not true? [ AIEEE 2003]
  • a)Optical fibers can be of graded refractive index
  • b) Optical fibers are subject to electromagnetic interference from outside
  • c)optical fibers have extremely low transmission loss
  • d)Optical fibers may have homogeneous core with a suitable cladding
Q.28
To demonstrate the phenomenon of interference, we require two sources which emit radiation [ AIEEE 2003]
  • a) of nearly the same frequency
  • b) of the same frequency
  • c)of different wave lengths
  • d)of the same frequency and having a definite phase relationship
Q.29
The image formed by an objective of a compound microscope is [ AIEEE 2003]
  • a) virtual and diminished
  • b) real and diminished
  • c)real and enlarged
  • d)virtual and enlarged
Q.30
To get three images of single object, one should have two mirror at an angle of [ AIEEE 2003]
  • a) 60°
  • b) 90°
  • c) 120°
  • d) 30°
Q.31
A light ray is incident perpendicularly to one face of a 90° prism and is totally internally reflected at the glass-air interface. If the angle of reflection is 45°, we conclude that the refractive index n [ IIT 2004]
  • a)n > 1 /√2
  • b) n > √2
  • c)n < 1 /√2
  • d)n < √2
Q.32
A plano convex lens of refractive index 1.5 and radius of curvature 30cm. Is silvered at the curved surface. Now this lens has been used to form the image of an object. At what distance from this lens an object be placed in order to have a real image of size of object [ AIEEE 2004]
  • a) 60cm
  • b) 30 cm
  • c)20 cm
  • d)80 cm
Q.33
The maximum number of possible interference maxima for slit-separation equal to twice the wave length in Young's double-slit experiment is [ AIEEE 2004]
  • a) three
  • b) five
  • c) infinite
  • d) zero
Q.34
An electromagnetic wave of frequency f=3.0 MHz passes from vacuum into a dielectric medium with permittivity ε=4.Then [AIEEE 2004]
  • a)Wave length is halved and frequency remains unchanged
  • b) Wave length is doubled and frequency become half
  • c)Wave length is doubled and the frequency remains unchanged
  • d)Wave length and frequency both remains unchanged
Q.35
A fish looking up through the water sees the outside world contained in a circular horizon. If the refractive index of water is 4/3 and fish is 12 cm below the surface, the radius of this circle in cm is [ AIEEE 2005]
  • a) 36 / √7
  • b) 36√7
  • c)4√5
  • d)36√5
Q.36
The angle of prism is 30°. The rays incident at 60° on one refracting face suffer a deviation of 30°. Then the angle of emergence is [ EAMCT 1990]
  • a) 0°
  • b) 30°
  • c)60°
  • d)90°
Q.37
The correct relation between time interval δ and phase difference φ is
  • a)δ=(T/2π)φ
  • b) δ=(2π/T)φ
  • c)δ=2πφ
  • d)δ=φ/2π
Q.38
A thin glass ( refractive index 1.5) lens has optical power of -5D in air. Its optical power in a liquid medium with refractive index 1.6 will be [ AIEEE 2005]
  • a) -1D
  • b) 1D
  • c) -25D
  • d) 25D
Q.39
A Young's double slit experiment uses a monochromatic source. The shape of the interference fringes formed on screen is [ AIEEE 2005]
  • a) circle
  • b) hyperbola
  • c)parabola
  • d)straight line
Q.40
If Io is the intensity of the principal maximum in the single slit diffraction pattern, then what will be its intensity when the slit width is doubled? [ AIEEE 2005]
  • a) 4Io
  • b) Io/2
  • c) Io/2
  • d) Io
Q.41
The refractive index of glass is 1.52 for red light and 1.525 for blue light. Let D1 and D2 be angles of minimum deviation for red and blue light respectively in prism of this glass Then ..[ AIEEE 2006]
  • a) D1 < D2
  • c)D1 can be less than or greater than D2 depending upon the angle of prism
  • d) D1 > D2
  • b) D₁=D₂
Q.42
In a Young's double slit experiment the intensity at a point where the path difference is λ/6( λ being the wavelength of light used) is I. If Io denotes the maximum intensity, I/Io is equal to [ AIEEE 2007]
  • a) 3/4
  • b) 1 /√2
  • c) √3 / 2
  • d) 1/2
Q.43
Two lenses of power -15D and +D are in contact with each other. The focal length of combination is [ AIEEE 2007]
  • a)+10 cm
  • b) -20 cm
  • c)-10 cm
  • d)+ 20 cm
Q.44
In an experiment, electrons are made to pass through a narrow slit of width 'd' comparable to their de Broglie wave length. They are detected on screen at a distance 'D' from the slit ( see figure)Which of the following graphs can be expected to represent the number of electrons 'N' detected as a function of the detector position 'y' ( y=0 corresponds to the middle of the slit) [AIEEE 2007]
ch-11_que_no-126_img_no1.png
  • a)
    ch-11_qn-126choice_img_no1.png
  • b)
    ch-11_qn-126choice_img_no2.png
  • c)
    ch-11_qn-126choice_img_no3.png
  • d)
    ch-11_qn-126choice_img_no4.png
Q.45
A student measures the focal length of a convex lens by putting an object pin at a distance 'u' from the lens and measuring the distance 'v' of the image pin. The graph between 'u' and 'v' plotted by the student should look like[ AIEE 2008]
  • a)
    ch-11_qn-127choice_img_no1.png
  • b)
    ch-11_qn-127choice_img_no2.png
  • c)
    ch-11_qn-127choice_img_no3.png
  • d)
    ch-11_qn-127choice_img_no4.png
Q.46
An experiment is performed to find the refractive index of glass using a traveling microscope. in this experiment distances are measured by [ AIEE 2008]
  • a) a vernier scale provided on the microscope
  • b) a standard laboratory scale
  • c) a meter scale provided on the microscope
  • d) a screw gauge provided on the microscopes
Q.47
A mixture of light, consisting of wavelength 590nm and an unknown wavelength, illuminates Young's double slit and gives rise to two overlapping interference pattern on the screen. The central maximum of both lights coincide. Further, it is observed that the third bright fringe of known light coincides with 4th bright fringe of unknown light. From this data, the wavelength of the unknown light is [ AIEEE 2009]
  • a)885.0 nm
  • b) 442.5 nm
  • c)776.8 nm
  • d)393.4 nm
Q.48
A transparent solid cylindrical rod has a refractive index of 2/√It is surrounded by air. A light ray is incident at the mid-point of one end of the rod as shown in figure. The incident angle θ for which the light ray grazes along the wall of the rod is [ AIEEE 2009]
ch-11_que_no-130_img_no1.png
  • a) sin⁻¹(√3/2)
  • b) sin⁻¹(2/√3)
  • c)sin⁻¹(1/√3)
  • d)sin⁻¹(1/2)
Q.49
In an optical experiment, with the position of the object fixed, a student varies the position of a convex lens and for each position, the screen is adjusted to get a clear image of the object. A graph between the object distance u and the image distance v, from the lens, is plotted using the same scale for two axes. A straight line passing through the origin and makes an angle of 45° with the x-axis meets the experimental curve at P. The coordinates of P will be..[ AIEEE 2009]
  • a)( f/2 , f/2)
  • b) (f, f)
  • c)(4f, 4f0
  • d)(2f, 2f)
Q.50
A man 180 cm height stands in front of a plane mirror. His eyes are at a height of 170cm from floor. Then the minimum length of planer mirror from him to see his full length image is [ MPPMT 1993]
  • a) 90 cm
  • b) 180cm
  • c) 45 cm
  • d) 360 cm
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