31 In photo-electric effect, the energy of ejected electrons depends on .
(a) The intensity of light (b) The frequency of light
(c) Both intensity and frequency (d) Wave length of the above
31. Longitudinal waves do not exhibit (show)
(a) Reflection (b) Refraction
(c) Diffraction (d) Polarisation
32. The locus of all points in a medium having the same phase of
vibration is called
(a) Crest (b) Trough
(c) Wave length (d) Wave front
33. At a very large distance from a point source we get
(a) An elliptical wave front (b) A cylindrical wave front
(c) A plane wave front (d) A rectangular wave front
34. Huygen’s principle states that
- (a) Light travels in straight line
(b) Light travels in electromagnetic waves
(c) All points on primary wave front are source of secondary wavelets
(d) Light has dual nature
35. In order to get the interference of light waves
(a) The sources should be monochromatic
(b) The sources should be phase coherent
(c) The linear supper-position should be applicable
(d) All of the above
36. In Young’s double slit experiment, the condition for constructive
interference (or bright fringes ) is
(a) d sin() (m + 1/2)A (b) d sin() = mA
(c) d sin0 = Off — I/2)A (d) 2d sine = rnA
37. In Young’s double slit experiment, the fringe spacing (or fringe
width) is equal to
(a) d sin() -= Era (b) d sint9 = mA/2
• (c) d sin() = (m — 1/2).1 (d) d sin° = (m + 1/2)A
A. The velocity of light was determined accurately by
(a) Newton (b) Michelson
(c) l-lygen (d) Young
39. The condition for constructive interference of two coherent beams
is that the path difference should be
(a) Integral multiple of/1/2 (b) Integral ryultiple of).
(c) Odd integral multiple of Al2 (d) Even integral multiple of).
40. The condition for destructive interference of two coherent waves is
that the oath difference should be
(a) Integral multiple of A/2 (b) Integral multiple of .A.
(c) Odd integral multiple of A/2 (d) Even integral multiple of Al2
31. | d | 32. |
d |
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33. |
c |
34. |
c |
35. | d | 36. |
b |
37. |
c |
38. |
b |
39. | b | 40. |
c |