In Young's double slit experiment, if the slit widths are in the ratio 1 : 9, then the ratio of the intensity at minima to that at maxima will be 

  • 1

  • 1/9

  • 1/4

  • 1/3

In a certain double slit experimental arrangement interference fringes of width 1.0 mm each are observed when light of wavelength 5000 Å is used. Keeping the set up unaltered, if the source is replaced by another source of wavelength 6000 Å, the fringe width will be 

  • 0.5 mm

  • 1.0 mm

  • 1.2 mm

  • 1.5 mm

Two coherent light sources S1 and S2 (λ= 6000 Å) are 1mm apart from each other. The screen is placed at a distance of 25 cm from the sources. The width of the fringes on the screen should be 

  • 0.015 cm

  • 0.025 cm

  • 0.010 cm

  • 0.030 cm

The figure shows a double slit experiment P and Q are the slits. The path lengths PX and QX are nλ and (n + 2) λ respectively, where n is a whole number and λ is the wavelength. Taking the central fringe as zero, what is formed at X

  • First bright

  • First dark

  • Second bright

  • Second dark

The Young's experiment is performed with the lights of blue (λ = 4360 Å) and green colour (λ = 5460 Å), If the distance of the 4th fringe from the centre is x, then 

  • x (Blue) = x (Green)

  • x (Blue) > x (Green)

  • x (Blue) < x (Green)

  • x(Blue)x(Green)=54604360

In Young's double slit experiment, if L is the distance between the slits and the screen upon which interference pattern is observed, x is the average distance between the adjacent fringes and d being the slit separation. The wavelength of light is given by 

  • xdL

  • xLd

  • Ldx

  • 1Ldx

In Young's experiment, light of wavelength 4000 Å is used to produce bright fringes of width 0.6 mm, at a distance of 2 meters. If the whole apparatus is dipped in a liquid of refractive index 1.5, then fringe width will be 

  • 0.2 mm

  • 0.3 mm

  • 0.4 mm

  • 1.2 mm

In Young's double-slit experiment, the phase difference between the light waves reaching the third bright fringe from the central fringe will be (λ =6000 Å ) 

  • Zero

  • 2π

  • 4π

  • 6π

In two separate set-ups of the Young's double slit experiment, fringes of equal width are observed when lights of wavelengths in the ratio 1 : 2 are used. If the ratio of the slit separation in the two cases is 2 : 1, the ratio of the distances between the plane of the slits and the screen in the two set-ups is- 

  • 4 : 1

  • 1 : 1

  • 1 : 4

  • 2 : 1

In a biprism experiment, by using light of wavelength 5000 Å, 5 mm wide fringes are obtained on a screen 1.0 m away from the coherent sources. The separation between the two coherent sources is

  • (1) 0 mm

  • (2) 0.1 mm

  • (3) 0.05 mm

  • (4) 0.01 mm

The slits in Young's double-slit experiment have equal widths and the source is placed symmetrically relative to the slits. The intensity at the central fringe is I0. If one of the slits is closed, the intensity at this point will be:

  • I0

  • I0 / 4

  • I0 / 2

  • 4I0

A thin mica sheet of thickness 2×10–6 m and refractive index (μ = 1.5) is introduced in the path of the first wave. The wavelength of the wave used is 5000 Å. The central bright maximum will shift 

  • 2 fringes upward

  • 2 fringes downward

  • 10 fringes upward

  • None of these

If the separation between screen and source is increased by 2% what would be the effect on the intensity?

  • Increases by 4%

  • Increases by 2%

  • Decreases by 2%

  • Decreases by 4%

In Young's double slit experiment, 62 fringes are seen in visible region for sodium light of wavelength 5893 Å. If violet light of wavelength 4358 Å is used in place of sodium light, then number of fringes seen will be 

  • 54

  • 64

  • 74

  • 84

In Young's double slit experiment, angular width of fringes is 0.20o for sodium light of wavelength 5890 Å. If complete system is dipped in water, then angular width of fringes becomes 

  • 0.11o

  • 0.15o

  • 0.22o

  • 0.30o

In Young's double slit experiment, the distance between the two slits is 0.1 mm and the wavelength of light used is 4×10–7 m. If the width of the fringe on the screen is 4 mm, the distance between screen and slit is 

  • 0.1 mm

  • 1 cm

  • 0.1 cm

  • 1 m

In Young's double slit experiment using sodium light (λ = 5898 Å), 92 fringes are seen. If given colour (λ = 5461 Å) is used, how many fringes will be seen 

  • 62

  • 67

  • 85

  • 99

In Young’s experiment, the distance between slits is 0.28 mm and distance between slits and screen is 1.4 m. Distance between central bright fringe and third bright fringe is 0.9 cm. What is the wavelength of used light 

  • 5000 Å

  • 6000 Å

  • 7000 Å

  • 9000 Å

If a transparent medium of refractive index μ = 1.5 and thickness t = 2.5 × 10–5 m is inserted in front of one of the slits of Young’s Double Slit experiment, how much will be the shift in the interference pattern? The distance between the slits is 0.5 mm and that between slits and screen is 100 cm 

  • 5 cm

  • 2.5 cm

  • 0.25 cm

  • 0.1 cm

In Young’s experiment, monochromatic light is used to illuminate the two slits A and B. Interference fringes are observed on a screen placed in front of the slits. Now if a thin glass plate is placed normally in the path of the beam coming from the slit 

  • The fringes will disappear

  • The fringe width will increase

  • The fringe width will decrease

  • There will be no change in the fringe width but the pattern shifts

Two slits, 4 mm apart, are illuminated by light of wavelength 6000 Å. What will be the fringe width on a screen placed 2m from the slits 

  • 0.12 mm

  • 0.3 mm

  • 3.0 mm

  • 4.0 mm

In the Young’s double slit experiment with sodium light. The slits are 0.589 m a part. The angular separation of the third maximum from the central maximum will be (given λ = 589 nm) 

  • sin−1(0.33×108)

  • sin−1(0.33×10−6)

  • sin−1(3×10−8)

  • sin−1(3×10−6)

If the sodium light in Young’s double slit experiment is replaced by red light, the fringe width will

  • Decrease

  • Increase

  • Remain unaffected

  • First increase, then decrease

In Young’s double-slit experiment the wavelength of light was changed from 7000 Å to 3500 Å. While doubling the separation between the slits which of the following is not true for this experiment:

  • The width of the fringes changes

  • The colour of bright fringes changes

  • The separation between successive bright fringes changes

  • The separation between successive dark fringes remains unchanged

In Young’s double-slit experiment, an interference pattern is obtained on a screen by a light of wavelength 6000 Å, coming from the coherent sources S1 and S2. At certain point P on the screen third dark fringe is formed. Then the path difference S1P – S2P in microns is 

  • 0.75

  • 1.5

  • 3.0

  • 4.5

In Young’s double-slit experiment the fringe width is β. If entire arrangement is placed in a liquid of refractive index n, the fringe width becomes 

  • βn+1

  • nβ

  • βn

  • βn−1

In Young’s double slit experiment, distance between two sources is 0.1 mm. The distance of screen from the sources is 20 cm. Wavelength of light used is 5460 Å. Then angular position of the first dark fringe is 

  • 0.08°

  • 0.16°

  • 0.20°

  • 0.32°

In a Young’s double slit experiment, the slit separation is 0.2 cm, the distance between the screen and slit is 1m. Wavelength of the light used is 5000 Å. The distance between two consecutive dark fringes (in mm) is 

  • 0.25

  • 0.26

  • 0.27

  • 0.28

A star emitting light of wavelength 5896 Å is moving away from the earth with a speed of 3600 km/sec. The wavelength of light observed on earth will 

(3) Decrease by 70.75 Å

  • Decrease by 5825.25 Å

  • Increase by 5966.75 Å

  • (c = 3 × 108 m/sec is the speed of light)

  • Increase by 70.75 Å

A heavenly body is receding away from the earth such that the fractional change in λ is 1, then its velocity is :

  • C

  • 3C5

  • C5

  • 2C5

0:0:1


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