Ray Optics and Optical Instruments MCQ Questions Class 12 Physics Chapter 9
NCERT MCQ Questions for Class 12 Physics Chapter 9 Ray Optics and Optical Instruments. Ray Optics and Optical Instruments MCQ Questions with Answers from Class 12 Physics.
Ray Optics and Optical Instruments MCQ Questions Class 12 Physics Chapter 9
Ray Optics and Optical Instruments Multiple Choice Questions with Answers Class 12 Physics Chapter 9 PDF is available.
1) The electromagnetic radiation belonging to the region of spectrum 400nm – 700nm is called as
a) Microwave
b) Infrared
c) Light
d) Gamma rays
Ans: c) light
2) The speed of light in vacuum is given as
a) 3*10-8 m/s
b) 3*108 km/s
c) 3*108 m/s
d) None
Ans: c) 3*108 m/s
3) The bundle of rays of light constitute to form the
a) Bundle of light
b) Packets of light
c) Both a and b
d) Beam of light
Ans: d) beam of light
4) The geometric centre of the spherical mirror is called as
a) Pole of the mirror
b) Optical centre
c) Centre of curvature
d) None
Ans: a) pole of the mirror
5) The geometric centre of spherical lens is called as
a) Pole of the mirror
b) Optical centre
c) Centre of curvature
d) None
Ans: b) optical centre
6) In spherical mirror, the line joining pole and the centre of curvature is called as
a) Optical axis
b) Principal axis
c) Major axis
d) None
Ans: b) principal axis
7) In case of spherical lenses, the line joining optical centre with its principal focus is called as
a) Optical axis
b) Principal axis
c) Principal radius
d) Radius of curvature
Ans: b) principal axis
8) The distances measured in the same direction as the incident light are taken as
a) Negative
b) Positive
c) Both a and b
d) None
Ans: b) positive
9) The distances measured in the direction opposite to the direction of incident light are taken as
a) Positive
b) Negative
c) Both a and b
d) None
Ans: b) negative
10) The heights measured upward with respect to X axis and normal to the principal axis of mirror or lens are taken as
a) Positive
b) Negative
c) Both a and b
d) None
Ans: a) positive
11) The heights measured downward with respect to X axis and normal to the principal axis of mirror or lens are taken as
a) Positive
b) Negative
c) Both a and b
d) None
Ans: b) negative
12) In case of concave mirror, the reflected rays converge at a point on the principal axis which is called as
a) Focus
b) Principal focus
c) Optical centre
d) Pole
Ans: b) principal focus
13) In case of convex mirror, the reflected rays appear to diverge from the point on the principal axis which is called as
a) Pole of the mirror
b) Optical centre
c) Principal focus
d) None
Ans: c) principal focus
14) The distance between the principal focus F and pole of the mirror P is called as
a) Optical radius
b) Principal radius
c) Focal length
d) None
Ans: c) focal length
15) If f is the focal length of the mirror then R = 2f, R is called as
a) Principal radius
b) Radius of curvature
c) Both a and b
d) None
Ans: b) radius of curvature
16) If the rays originating from the point, actually meet at another point after reflection or refraction then that point is called as
a) Object of first point
b) Image of first point
c) Both a and b
d) None
Ans: b) image of first point
17) If the rays actually converge at a point after reflection or refraction then the image will be
a) Real image
b) Imaginary image
c) Both a and b
d) None
Ans: a) real image
18) If the rays do not actually meet but appear to diverge from the point when produced backwards then the image formed will be
a) Real image
b) Imaginary image
c) Both a and b
d) None
Ans: b) imaginary image
19) If the incident ray is parallel to the principal axis then after reflection
a) It doesn’t go through the focus of the mirror
b) It go through the focus of the mirror
c) It go through the pole of the mirror
d) None
Ans: b) it go through the focus of the mirror
20) If the ray of light is passing through the centre of curvature of a concave mirror or appearing to pass through centre of curvature in convex mirror then
a) Reflected ray pass through the focus
b) Reflected ray simply retraces it’s path
c) Reflected ray doesn’t pass through the focus
d) Reflected ray does not retraces it’s path
Ans: b) reflected ray simply retraces it’s path
21) If the ray of light passing through the focus of the concave mirror or appearing to pass through the focus of the convex mirror then
a) Reflected ray simply retraces it’s path
b) Reflected ray is parallel to principal axis
c) Both a and b
d) Reflected ray is not parallel to principal axis
Ans: b) reflected ray is parallel to principal axis
22) The ray of light incident at any angle at the pole then reflected ray
a) Doesn’t follows laws of reflection
b) Follow laws of reflection
c) Both a and b
d) None
Ans: b) follows laws of reflection
23) The mirror formula is given by
a) 1/f = 1/v – 1/u
b) 1/v = 1/f -1/u
c) 1/f = 1/v + 1/u
d) None
Ans: c) 1/f = 1/v + 1/u
24) The magnification in case of mirror is given by
a) M = object height/image height
b) M= image height/object height
c) M= -v/u
d) Both b and c
Ans: d) both b and c
25) The ray of light traveling from one transparent medium to another changes its direction of path in the second medium, this is called as
a) Reflection
b) Refraction
c) Dispersion
d) Polarisation
Ans: b) refraction
26) The incident ray, refracted ray and normal to the interface at the point of incidence all
a) Do not lie in the same plane
b) Lie in the same plane
c) Both a and b
d) None
Ans: b) lie in the same plane
27) The angle made by incident ray with the normal is called as
a) Angle of reflection
b) Angle of deviations
c) Angle of incidence
d) Angle of refraction
Ans: c) angle of incidence
28) The angle made by refracted ray with the normal is called as
a) Angle of reflection
b) Angle of deviations
c) Angle of incidence
d) Angle of refraction
Ans: d) angle of refraction
29) The angle made by reflected ray with the normal is called as
a) Angle of reflection
b) Angle of incidence
c) Angle of deviations
d) Angle of refraction
Ans: a) angle of reflection
30) The angle made by incident ray with the interface separating two mafia is called as
a) Angle of deviations
b) Angle of incidence
c) Glancing angle
d) None
Ans: c) glancing angle
31) The ratio of sine of angle of incidence to the sine of angle of refraction remains constant for given pair of media and that constant is called as
a) Refractive index
b) Refractive index of first medium with respect to second medium
c) Refractive index of second medium with respect to first medium
d) None
Ans: c) refractive index of the second medium with respect to first medium
32) The ray of light traveling from rarer medium to denser medium
a) Bends away from the normal
b) Bends towards the normal
c) Does not changes its path
d) None
Ans: b) bends towards the normal
33) The ray of light traveling from denser medium to rarer medium
a) Bends away from the normal
b) Bends towards the normal
c) Does not changed its path
d) None
Ans: a) bends away from the normal
34) Denser medium has _____ optical density than the rarer medium.
a) Less
b) More
c) Zero
d) None
Ans: b) more
35) In case of refraction of light through parallel sided glass slab, the emergent ray is
a) Parallel to refracted ray
b) Not parallel to incident ray
c) Parallel to incident ray
d) None
Ans: c) parallel to incident ray
- In case you have missed:- Previous Chapter MCQ Questions
36) The bottom of the tank filled with water appear to be raised due to
a) Reflection
b) Dispersion
c) Refraction
d) Polarisation
Ans: c) refraction
37) The sun is visible a little before actual sunrise and untill a little after the actual sunset due to
a) Atmospheric reflection
b) Atmospheric scattering
c) Atmospheric refraction
d) Both b and c
Ans: c) atmospheric refraction
38) When a ray of light traveling from denser medium to rarer medium it get partly reflected back into the same medium and partly refracted to the second medium, this is called as
a) External reflection
b) Internal reflection
c) Both a and b
d) Total internal reflection
Ans: b) internal reflection
39) The angle of incidence corresponding to an angle of refraction 90° is called as
a) Emerging angle
b) Deviation angle
c) Particular angle
d) Critical angle
Ans: d) critical angle
40) The refractive index of the diamond is
a) 1.52
b) 1.62
c) 2.42
d) None
Ans: c) 2.42
41) Which of the following shows total internal reflection
a) Mirage
b) Prism
c) Diamond
d) All
Ans: d) all
42) The light traveling through optical fibres is due to
a) Internal reflection
b) Total internal reflection
c) Refraction
d) Scattering
Ans: b) total internal reflection
43) The lens formula is given by
a) 1/f = 1/v + 1/u
b) 1/f = 1/v – 1/u
c) 1/v = 1/f – 1/u
d) None
Ans: b) 1/f = 1/v – 1/u
44) The focus on the side of the original source of light is called as____ whereas the focus on the other side is called as___
a) Second focal point, first focal point
b) First focal point, second focal point
c) Both a and b
d) None
Ans: b) first focal point, second focal point
45) The ray of light passing through the optical centre of the lens after refraction
a) Emerges with deviation
b) Emerges without deviations
c) Both a and b
d) None
Ans: b) emerges without deviation
46) Magnification in case of lenses is given by
a) M = image height/ object height
b) M= -v/u
c) M= v/u
d) Both a and c
Ans: d) both a and c
47) The measure of convergence or divergence of a lens which a lens introduces in the light falling on it is called as
a) Power of lens
b) Optical density of lens
c) Magnification of lens
d) None
Ans: a) power of lens
48) A lens of shorter focal length bends
a) Incident light less
b) Reflected light more
c) Incident light more
d) None
Ans: c) incident light more
49) The SI unit of power of lens is
a) Watt
b) Joule
c) Dioptre
d) None
Ans: c) dioptre
50) 1D =
a) 1m
b) 1cm
c) 1m-1
d) 1cm-1
Ans: c) 1m-1
51) The power of lens is given as
a) P= 1/f
b) F= 1/P
c) Both a and b
d) P= 2f
Ans: c) both a and b
52) If the power of the lens is +2.5D then it’s focal length will be
a) -40cm
b) 40cm
c) -40m
d) 40m
Ans: b) 40cm
53) If the power of the lens is -4.0 D then it’s focal length is
a) 25cm
b) -25cm
c) 25m
d) -25m
Ans: b) -25cm
54) If the any number of thin lenses in contact of focal length f1, f2, .. then effective focal length of their combination is given by
a) 1/f = 1/f1 + 1/f2 + …
b) f = f1 + f2 + …
c) f = f1 – f2 -…
d) 1/f = 1/f1 – 1/f2 -…
Ans: a) 1/f = 1/f1 + 1/f2 + …
55) If the any number of thin lenses are in contact having power as P1, P2,… then effective power of their combination is given by
a) 1/P = 1/P1 + 1/P2 +…
b) P= P1 + P2 + …
c) P = P1 – P2 – P3-…
d) 1/P = 1/P1 – 1/P2 -..
Ans: b) P= P1 + P2 + …
56) If the may number of thin lenses are in contact having magnification m1, m2,… then effective magnification of their combination is given by
a) M= m1*m2*..
b) M= 1/m1*1/m2*…
c) M= m1 – m2 – …
d) M= m1 + m2 +…
Ans: a) M = m1*m2*m3*…
57) The system of combination of lenses is commonly used in designing lenses for
a) Microscopes
b) Telescope
c) Cameras
d) All
Ans: d) all
58) In case of prism, the angle between emergent ray and the direction of incident ray is called as
a) Glancing angle
b) Refracting angle
c) Angle of deviation
d) None
Ans: c) angle of deviation
59) The angle of deviation depends on the
a) Angle of refraction
b) Angle of incidence
c) Both a and b
d) None
Ans: b) angle of incidence
60) The dispersion takes place because
a) Refractive index of medium is same for different frequencies
b) Refractive index of medium is different for different frequencies
c) Both a and b
d) None
Ans: b) refractive index of medium is different for different frequencies
61) Thick lenses shows chromatic aberration due to
a) Refraction of light
b) Scattering of light
c) Dispersion of light
d) Total internal reflection of light
Ans: c) dispersion of light
62) The rainbow is the example of _____ of sunlight by the water drops in the atmosphere.
a) Refraction
b) Scattering
c) Reflection
d) Dispersion
Ans: d) dispersion
63) Light of shorter wavelength is scattered ____ than the light of longer wavelength.
a) Less
b) Much more
c) Both a and b
d) None
Ans: b) much more
64) The amount of scattering is inversely proportional to
a) Cube of wavelength
b) Square of wavelength
c) Fourth power of wavelength
d) None
Ans: c) fourth power of wavelength
65) The amount of scattering is inversely proportional to fourth power of wavelength is called as
a) Rayleigh’s dispersion
b) Rayleigh’s scattering
c) Rayleigh’s reflection
d) None
Ans: b) Rayleigh’s scattering
66) A simple magnifier or microscope is a
a) Diverging lens of small focal length
b) Converging lens of small focal length
c) Diverging lens of large focal length
d) Converging lens of large focal length
Ans: b) converging lens of small focal length
67) The magnification formula for microscope is given by
a) M = ( 1 + f/D)
b) M = ( 1 – D/f)
c) M = (1 + D/f)
d) None
Ans: c) M = (1 + D/f)
68) For much larger magnification, one uses two lenses, one compounding the effect of the other and it is known as
a) Microscope
b) Compound microscope
c) Both a and b
d) Telescope
Ans: b) compound microscope
69) In compound microscope, the lens nearest to object is called as
a) Objective
b) Eyepiece
c) Both a and b
d) None
Ans: a) objective
70) The _____ is used to provide angular magnification of distant objects.
a) Microscope
b) Compound microscope
c) Telescope
d) None
Ans: c) telescope
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