Q.1
A beam of light incident on a plane mirror form a real image on reflection. The incident beam is ..[ MPPMT 1997]
  • a)parallel
  • b) convergent
  • c)divergent
  • d)none of the above
Q.2
A concave mirror has radius of curvature of 1m. Light from a distant star is incident on the mirror. the distance of the image of star from the mirror is
  • a) 0.5 m
  • b) 1.0 m
  • c)2.0 m
  • d)0.25m
Q.3
Plane mirrors A and B are kept at an angle of θ, with respect to each other. Light falls on A, is reflected, then falls on B and is reflected. then emergent ray is opposite to the incident direction. Then the angle θ is equal to ...[ SCRA 1994]
  • a) 45°
  • b) 30°
  • c)60°
  • d)90°
Q.4
An object 1 cm tall is placed 4cm in front of a mirror. in order to produce an upright image of 3cm height one needs a .. [ SCRA 1994]
  • a) convex mirror of radius of curvature 12 cm
  • b) concave mirror of radius of curvature 12 cm
  • c)concave mirror of radius of curvature 4 cm
  • d)plane mirror of height 120 cm
Q.5
A clock hung on a wall has marked instead of numerals on its dial. On the adjoining wall, there is a plane mirror and image of the clock in the mirror indicates the time 3:Then the time in the clock is [ Raj.PET 1997]
  • a) 7:40
  • b) 8:35
  • c) 2:40
  • d) 4:07
Q.6
A concave mirror of radius of curvature 60 cms is placed at the bottom of a tank, containing water upto height of 20cms. The mirror faces upwards with its axis vertical. Solar light falls normally on the surface of water and the image of sun is formed. If n=4/3, then with the observer in air, the distance of the image from the surface of water is
  • a)30 cms
  • b) 7.5 cm above
  • c)10 cm
  • d)7.5 cm below
Q.7
A light wave is incident over a plane surface with velocity V. After reflection the velocity will become [ Raj. PMT 1996]
  • a) V
  • b) 2V
  • c)3V
  • d)4V
Q.8
A short linear object of length b lies along the axis of a concave mirror of focal length f at a distance u from the pole of the mirror. The size of the image is approximately equal to ..[ IIT 1988]
  • a)
    ch-11_qn-139choice_img_no1.png
  • b)
    ch-11_qn-139choice_img_no2.png
  • c)
    ch-11_qn-139choice_img_no3.png
  • d)
    ch-11_qn-139choice_img_no4.png
Q.9
A biconvex lens forms a real image of an object placed perpendicular to its principal axis. Suppose the radii of curvature of the lens tend to infinity. Then the image would [ MPPMT 1994]
  • a) disappear
  • b) remains as real image still
  • c) be virtual and of same size as the object
  • d) suffer from aberrations
Q.10
A glass slab of thickness 4cm contains the same number of waves as X cm of water column when both are traversed by the same monochromatic light. If the refractive indices of glass and water ( for that light) are 5/3 and 4/3 respectively, the value of X will be [ Raj.PMT 1997]
  • a)9/20 cm
  • b) 20/9 cm
  • c)5/4 cm
  • d)5 cm
Q.11
The critical angle for total internal reflection of light going from medium I to medium II is given by the relation tan C=5/The refractive index of the medium I with respect to medium II is
  • a) 1.4
  • b) 1.6
  • c)(√74)/5
  • d)5 / (√79)
Q.12
A beam of light consisting of red, green and blue colors is incident on a right-angled prism. The refractive indices of the material of the prism for the above red, green, an blue wave-lengths are 1.39, 1.44 and 1.47 respectively. The prism will [ CPMT 1998]
  • a) separate part of the red color from green and blue colors
  • b)separate part of the blue colors from the red and blue colors
  • c)separate all the three colors from one another
  • d)not separate even partially any color from the other two colors
Q.13
A vessel of depth d cm is half filled with a liquid of refractive index n1 and the upper half with refractive index nthe apparent depth of the vessel seen perpendicularly is [ SCRA 1994]
  • a)
    ch-11_qn-144choice_img_no1.png
  • b)
    ch-11_qn-144choice_img_no2.png
  • c)
    ch-11_qn-144choice_img_no3.png
  • d)
    ch-11_qn-144choice_img_no4.png
Q.14
When a ray of light enters a glass slab from air [ IIT 1989]
  • a)Its wave length decreases
  • b) Its wavelength increases
  • c)Remains the same
  • d)Its frequency increases
Q.15
A beam of light is converging towards a point I on the screen. A plane parallel plate of glass whose thickness in the direction of beam is=t, refractive index=n, is introduced in the path of the beam. The convergence point is shifted by [ MNR 1987]
  • a)
    ch-11_qn-146choice_img_no1.png
  • b)
    ch-11_qn-146choice_img_no2.png
  • c)
    ch-11_qn-146choice_img_no3.png
  • d)
    ch-11_qn-146choice_img_no4.png
Q.16
Light travels through a glass plate of thickness t and having refractive index n. If c is the velocity of light in vacuum, the time taken by the light to travel this thickness of glass is ..[ MPPMT 1999]
  • a) t/nc
  • b) tnc
  • c)nt/c
  • d)tc/n
Q.17
A thin prism P1 with angle 4° and made from glass of refractive index 1.54 is combined with another thin prism P2 made from glass of refractive index 1.72 to produce dispersion without deviation. The angle of the prism P2 is [ MPPMT 1999]
  • a) 5.33°
  • b) 4°
  • c) 3°
  • d) 2.6°
Q.18
When light is incident on a medium at angle i and refracted into second medium at an angle r, the graph of sin i vs sin r is as shown in the graph. From this, one conclude that [ MPPET 1999]
ch-11_que_no-149_img_no1.png
  • a)velocity of light in the second medium is 1.73 times the velocity of light in the first medium
  • b) Velocity of light in the first medium is 2.73 times the velocity in the second medium
  • c)The critical angle for two medium is given by sinC=1 / √3
  • d)sinC=1/2
Q.19
Even in absolutely clear water a diver cannot see very clear
  • a) because rays of light get diffused in water
  • b) because velocity of light is reduced in water
  • c)because the rays of light passing through water make it turbid
  • d)because the focal length of the eye lens in water gets changed and the image is no longer focused on the retina
Q.20
The refracting angle of prism is A and refractive index of material of prism is cot(A/2). The angle of minimum deviation is [ CPMT 1992]
  • a) 180° - 3A
  • b) 180° + 2A
  • c) 90° - A
  • d) 180° - 2A
Q.21
There glass prisms A, B, C of same refractive index are paced in contact with each other as shown in figure with no air gap between the prisms. Monochromatic light Op passes through the prism assembly and emerges as QR. The condition of minimum deviation is satisfied in the prisms..[ CPMT]
ch-11_que_no-153_img_no1.png
  • a)A and C
  • b) B and C
  • c)A and B
  • d)In all prisms A, B and C
Q.22
A ray of light i incident at angle of 60° on one face of a prism which has an angle of 30°. The ray emerging out of the prism makes an angle of 30° with the incident ray. The refractive index of material of the prism is
  • a) √2
  • b) √3
  • c)1.5
  • d)1.6
Q.23
If refractive index of red, violet and yellow lights are 1.42, 1.62 and 1.5 respectively for a medium, its dispersible power will be [ Raj.PMT 1997]
  • a) 0.4
  • b) 0.3
  • c) 0.2
  • d) 0.1
Q.24
When light enters from air to water, then its [ MPPMT 1994]
  • a)frequency increases and speed decreases
  • b) frequency is same but the wavelength is smaller in water than in air
  • c)frequency is same but wave length in water is grater than in air
  • d)frequency decreases and wavelength is smaller in water than in air
Q.25
A ray of light passes through an equilateral prism such that the angle of incidence is equal to the angle of emergence and latter is equal to (3/4) the angle of the prism. The angle of deviation will be [ MPPMT 1999]
  • a) 45°
  • b) 39°
  • c)20°
  • d)30°
Q.26
If εo and µo are respectively, the electric permittivity and magnetic permeability of free space, ε and µ the corresponding quantities in a medium, the refractive index of the medium is [ CBSE 1997]
  • a)
    ch-11_qn-159choice_img_no1.png
  • b)
    ch-11_qn-159choice_img_no2.png
  • c)
    ch-11_qn-159choice_img_no3.png
  • d)
    ch-11_qn-159choice_img_no4.png
Q.27
A beam of monochromatic light blue light of wave length 4200Å in air travels in water ( refractive index n=4/3). Its wavelength in water will be [ MNR 1991]
  • a) 2800Å
  • b) 5600Å
  • c) 3150Å
  • d) 4000Å
Q.28
Light enters at an angle of incidence in a transparent rod of refractive index n. For what value of the refractive index of the material of rod, the light once entered into it will leave it through its lateral face. What so ever be the angle of incidence
  • a)n > √2
  • b) n=1.33
  • c)n=1
  • d)n=1.1
Q.29
A point source of light is placed 4m below the surface of water of refractive index 5/The minimum diameter of disc, which should be placed over the source, on the surface of water to cut off all light coming out of water is [ CBSE 1994]
  • a) ∞
  • b) 6 m
  • c)4 m
  • d)3 m
Q.30
A fish in water sees an object 24 cm above the surface of water. The height of object above surface of water will appear to fish. ( Refractive index of water 4/3) [ CPMT 1993]
  • a) 24 cm
  • b) 32 cm
  • c)18 cm
  • d)48 cm
Q.31
The angle of prism is 60°. What is the angle of incidence for minimum deviation? the refractive index of material of prism is √2 [ CPMT 1993]
  • a) 45°
  • b) 60°
  • c) 30°
  • d) sin⁻¹(2/3)
Q.32
Light rays from source are incident on glass prism of index of refraction µ and angle of prism α. At near normal incidence, the angle of deviation of emerging rays is [ MPPMT 1993]
  • a)(µ - 2)α
  • b) (µ - 1)α
  • c)(µ + 1)α
  • d)(µ + 2)α
Q.33
For total internal reflection to take place, the angle of incidence i and the refractive index µ of the medium must satisfy the inequality
  • c)sin i < µ
  • d)sini > µ
  • a) sin⁻¹ i < µ
  • b) sin⁻¹ i > µ
Q.34
Focal length of convex lens will be maximum for [ MPPMT 1994]
  • a)blue light
  • b) yellow light
  • c)green light
  • d) red light
Q.35
The plane surface of plano-convex lens of focal length f is silvered. It will behave as [ MPPMT]
  • a) plane mirror
  • b) convex mirror of focal length 2f
  • c) concave mirror with focal length f/2
  • d) none of above
Q.36
A dice is placed with its one edge parallel to the principle axis between the principal focus and the centre of curvature. The the image has the shape of :
  • a)Cube
  • b) Rectangular parallelopiped
  • c)Barrel shaped
  • d)spherical
Q.37
An observer moves towards a plane mirror with speed of 2m/s. The speed of the image with respect to the observer is ..
  • a) 2 m/s
  • b) 4m/s
  • c)1 m/s
  • d)3 m/s
Q.38
A person standing in front of mirror finds his image thinner but with normal height. this implies that the mirror is
  • a) convex and spherical
  • b) concave and spherical
  • c)Convex and cylindrical with axis vertical
  • d)Convex and cylindrical with axis horizontal
Q.39
A point object is placed mid-way between two plane mirror distance 'a' apart. the plane mirror forms an infinite number of images due to multiple reflection. The distance between the nth order image formed in the two mirrors is
  • a) na
  • b) 2na
  • c) na/2
  • d) n2a
Q.40
A convergent beam of light converges to a point 20cm behind the convex mirror on the principle axis. An inverted image of the same size is coincident with the virtual object. Then the focal length of the convex mirror is
  • a)20 cm
  • b) 10 cm
  • c)40 cm
  • d)30 cm
Q.41
Rays of light strikes a horizontal plane mirror at an angle of 45°. A second plane mirror is arranged at an angle θ with it. If the ray after reflection from the second mirror runs horizontally i.e. parallel to the first mirror then θ is
  • a) 45°
  • b) 60°
  • c)67°30'
  • d)135°
Q.42
A diminished virtual image can be obtained only in
  • a) A plane mirror
  • b) A concave spherical mirror
  • c)A convex spherical mirror
  • d)A concave spherical mirror
Q.43
A convergent beam of light is incident on a convex mirror of radius of curvature 0.6m as shown in figure. The image formed by the convex mirror is
ch-11_que_no-176_img_no1.png
  • a) Virtual and 15 cm behind the mirror
  • b) Real and 15 cm in front of the mirror
  • c) Virtual and 7.5 cm behind the mirror
  • d) Real and 7.5 cm in front of the mirror
Q.44
A ray of light is incident on a plane mirror at an angle of incidence of 30°. The deviation produced by the mirror is :
  • a)30°
  • b) 90°
  • c)120 °
  • d)60 °
Q.45
A small piece of wire bent into an L shape with upright and horizontal portions of equal lengths, is placed with the horizontal portion along the axis of the concave mirror whose radius of curvature is 10 cm. If the bend is 20 cm from the pole of the mirror, then the ratio of the lengths of the image of the upright and horizontal portions of the wire is
  • a) 1:2
  • b) 3:1
  • c)1:3
  • d)2 : 1
Q.46
The magnification m , the image position v and focal length f are related to one another by the relation
  • a)
    ch-11_qn-179choice_img_no1.png
  • b)
    ch-11_qn-179choice_img_no2.png
  • c)
    ch-11_qn-179choice_img_no3.png
  • d)
    ch-11_qn-179choice_img_no4.png
Q.47
The relation between magnification m, the objective position u and focal length f of the mirror is
  • a)
    ch-11_qn-180choice_img_no1.png
  • b)
    ch-11_qn-180choice_img_no2.png
  • c)
    ch-11_qn-180choice_img_no3.png
  • d)
    ch-11_qn-180choice_img_no4.png
Q.48
A concave mirror forms an errect image of twice its size, object distance from the mirror is
  • a)f/2
  • b) f/4
  • c) 3f/2
  • d)2f
Q.49
A convex mirror of focal length f produces an image (1/n)th of the size of the object. The distance of the object from the mirror is
  • a) ( n-1) f
  • b) ( n-1)f /n
  • c)( n+1)f /n
  • d)(n+1)f
Q.50
A person standing in the centre of a room, 12 m high looks into a plane mirror fixed on the wall. Then the minimum length of the plane mirror from him to see the full length image of the wall behind him, is equal to
  • a)12 m
  • b) 8 m
  • c)4 m
  • d)6 m
0 h : 0 m : 1 s