MCQs of Waves Optics

Waves Optics MCQs

MCQs of Waves Optics

Showing 41 to 50 out of 131 Questions

41.

To observe diffraction pattern, the size of an aperture should be _____.

(a)	exactly equal to $\frac{λ}{2}$
(b)	exactly equal to $2 λ$
(c)	of the same order as wavelength
(d)	much larger than the wavelength

42.

A beam of light of wavelength 600 nm from a distant source falls on a single slit 1 mm wide, and the resulting diffraction pattern is observed on a screen 2 m away. The distance between the first dark fringes on either side of the central fringe is _____

(a)	2.4 cm
(b)	2.4 mm
(c)	1.2 mm
(d)	1.2 cm

43.

In a linearly polarized light, magnitude of the electric field vector _____.

(a)	does not change with time
(b)	varies periodically with time
(c)	is parallel to the direction of its propagation
(d)	first increases and then decreases with the time

44.

In propagation of electromagnetic waves the angle between the direction of propagation and plane of polarization is _____.

(a)	0°
(b)	45°
(c)	90°
(d)	180°

45.

Which colour should be used to increase the resolving power of a microscope ?

(a)	violet
(b)	red
(c)	yellow
(d)	green

46.

Two stars at distance of two light years are just resolved by a telescope. The diameter of the telescope lens is 0.25 m. If the wavelength of light used in 5000 Å, then the minimum distance between the stars is _____.

(a)	1.22 × 10¹¹ m
(b)	2.44 × 10¹¹ m
(c)	3.66 × 10¹¹ m
(d)	4.88 × 10¹¹ m

47.

The diameter of an eye lens is 2.5 × 10^-3 m and the refractive index of the eye fluid is 1.44. The resolving power of the eye for light of wavelength 5000 Å will be _____(in minute^-1)

(a)	1.07
(b)	0.86
(c)	1.71
(d)	1.14

48.

Young's double slit experiment is performed using light of wavelength λ = 5000 Å, which emerges in phase from two slits at distance d = 3 × 10^-3 m apart. A transparent sheet of thickness t = 1.5 × 10^-3 m is covers one of the slits. The refractive index of the material of this sheet is μ = 1.17. The minimum shift in the central maximum of the interference pattern now appear at _____ (D = distance between screen and slits)

(a)	0.085D
(b)	D
(c)	1.2D
(d)	1.5D

49.

In a double slit experiment, instead of taking slits of equal width, one slit is made twice as wide as the other. Then in the interference pattern _____.

(a)	the intensities of both the maxima and the minima increase
(b)	the intensity of the maxima increases and the minima has zero intensity
(c)	the intensity of the maxima decreases and that of minima increases
(d)	the intensity of the maxima decreases and the minima has zero intensity

50.

What will be the value of slit width, if the first dark line is observed at an angle of 1° when light of 6000 Å is incident on it (sin1° = 0.0175)

(a)	0.034 mm
(b)	0.35 mm
(c)	0.34 mm
(d)	None of the above

Showing 41 to 50 out of 131 Questions