Wave Optics | Physics JEE previous year questions with Solutions

Q 1 :

The width of one of the two slits in a Young’s double slit experiment is 4 times that of the other slit. The ratio of the maximum to the minimum intensity in the interference pattern is [2024]

1 : 1
16 : 1
9 : 1
4 : 1

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4

(3)

$Since, Intensity \propto width of slit (W)$

So, $I_{1} = I_{0}, I_{2} = 4 I_{0}$

$\frac{I_{\max}}{I_{\min}} = \frac{{(\sqrt{I_{1}} + \sqrt{I_{2}})}^{2}}{{(\sqrt{I_{1}} - \sqrt{I_{2}})}^{2}} = \frac{9 I_{0}}{I_{0}} = 9$

Q 2 :

In Young's double slit experiment, light from two identical sources are superimposing on a screen. The path difference between the two lights reaching at a point on the screen is 7λ/4. The ratio of intensity of fringe at this point with respect to the maximum intensity of the fringe is [2024]

$\frac{1}{4}$
$\frac{1}{3}$
$\frac{3}{4}$
$\frac{1}{2}$

1

2

3

4

(4)

$Path difference, Δ x = \frac{7 λ}{4}$

$Phase difference, ϕ = \frac{2 π}{λ} Δ x = \frac{2 π}{λ} \times \frac{7 λ}{4} = \frac{7 π}{2}$

$Intensity, I = I_{\max} \cos^{2} (\frac{ϕ}{2})$

$\frac{I}{I_{\max}} = \cos^{2} (\frac{ϕ}{2}) = \cos^{2} (\frac{7 π}{2 \times 2}) = \cos^{2} (\frac{7 π}{4})$

$= \cos^{2} (2 π - \frac{π}{4}) = \cos^{2} \frac{π}{4} = \frac{1}{2}$

Q 3 :

Two wavelengths $λ_{1}$ and $λ_{2}$ are used in Young's double slit experiment. $λ_{1}$ = 450 nm and $λ_{2}$ = 650 nm. The minimum order of fringe produced by $λ_{2}$ which overlaps with the fringe produced by $λ_{1}$ is $n$ . The value of $n$ is ____. [2024]

(9) $m_{2} λ_{2} = m_{1} λ_{1}$

$\frac{m_{2}}{m_{1}} = \frac{λ_{1}}{λ_{2}} = \frac{450}{650} = \frac{9}{13}$

$i . e . 9^{th} maxima of λ_{2} overlaps with 13^{th} maxima of λ_{1} .$

$∴ n = 9$

Q 4 :

In Young’s double slit experiment, carried out with light of wavelength 5000 $Å$ , the distance between the slits is 0.3 mm and the screen is at 200 cm from the slits. The central maximum is at $x$ = 0 cm. The value of $x$ for the third maxima is __________ mm. [2024]

(10) $β = \frac{λ D}{d} = \frac{5 \times 10^{- 7} \times 2}{3 \times 10^{- 4}} = \frac{10 \times 10^{- 3}}{3} m$

$For 3^{rd} maxima y_{3} = 3 β = 10 \times 10^{- 3} m = 10 mm$

Q 5 :

Two slits are 1 mm apart and the screen is located 1 m away from the slits. A light of wavelength 500 nm is used. The width of each slit to obtain 10 maxima of the double slit pattern within the central maximum of the single slit pattern is ___ × $10^{- 4}$ m. [2024]

(2) $d = 1 m m,$ $D = 1 m,$ $λ = 500 n m$

$10 (\frac{λ D}{d}) = \frac{2 λ D}{a}$

$a = \frac{d}{5} = \frac{10 \times 10^{- 4} m}{5} = 2 \times 10^{- 4}$

Q 6 :

In a Young’s double slit experiment, the intensity at a point is ${(\frac{1}{4})}^{t h}$ of the maximum intensity. The minimum distance of the point from the central maximum is _____ µm.

(Given: $λ = 600 n m,$ $d = 1.0 m m,$ $D = 1.0 m$ ) [2024]

(200) $I = I_{0} \cos^{2} (\frac{Δ ϕ}{2})$

$\frac{1}{4} = \cos^{2} (\frac{Δ ϕ}{2})$

$Δ ϕ = \frac{2 π}{λ} Δ x \Rightarrow Δ ϕ = \frac{2 π}{3} = \frac{2 π}{λ} Δ x \Rightarrow Δ x = \frac{λ}{3}$

$\Rightarrow Δ x = \frac{d y}{D} = \frac{λ}{3}$

$\Rightarrow y = \frac{λ D}{3 d} = \frac{600 \times 10^{- 9} \times 1}{3 \times 10^{- 3}} = 2 \times 10^{- 4} m = 200 μ m$

Q 7 :

Monochromatic light of wavelength 500 nm is used in Young's double slit experiment. An interference pattern is obtained on a screen when one of the slits is covered with a very thin glass plate (refractive index = 1.5), the central maximum is shifted to a position previously occupied by the 4th bright fringe. The thickness of the glass plate is _____ µm. [2024]

(4) When glass plate is inserted, then the extra path difference will be

$(μ - 1) t = n λ$

$(1.5 - 1) t = 4 \times 500 \times 10^{- 9}$

$\Rightarrow t = \frac{4 \times 500 \times 10^{- 9}}{0.5} = 4 \times 10^{- 6} m = 4 μ m$

Q 8 :

In a double slit experiment shown in figure, when light of wavelength 400 nm is used, dark fringe is observed at P. If D = 0.2 m the minimum distance between the slits $S_{1}$ and $S_{2}$ is ____ mm. [2024]

(0.20)

Path difference for minima at P

$2 \sqrt{D^{2} + d^{2}} - 2 D = \frac{λ}{2}$

$∴$ $\sqrt{D^{2} + d^{2}} - D = \frac{λ}{4}$

$∴$ $\sqrt{D^{2} + d^{2}} = \frac{λ}{4} + D$

$\Rightarrow D^{2} + d^{2} = D^{2} + \frac{λ^{2}}{16} + \frac{D λ}{2}$

$\Rightarrow d^{2} = \frac{D λ}{2} + \frac{λ^{2}}{16}$

$= \frac{0.2 \times 400 \times 10^{- 9}}{2} + \frac{4 \times 10^{- 14}}{4} \Rightarrow d^{2} \approx 400 \times 10^{- 10}$

$∴$ $d = 20 \times 10^{- 5} \Rightarrow d = 0.20 mm$

Q 9 :

In Young’s double slit experiment, monochromatic light of wavelength 5000 $Å$ is used. The slits are 1.0 mm apart and the screen is placed at 1.0 m away from slits. The distance from the centre of the screen where intensity becomes half of the maximum intensity for the first time is ____ $\times 10^{- 6} m$ . [2024]

(125)

Let intensity of light on screen due to each slit is $I_{0}$

So, intensity at centre of screen is $4 I_{0}$

$λ = 5000 Å, d = 1 \times 10^{- 3} m$

$D = 1 m$

$Δ x = d \sin θ$ ...(i)

Let intensity of light on screen due to each slit is $I_{0}$

So intensity at centre of screen is $4 I_{0}$

$I_{\max} = 4 I_{0}$

$I_{\max} = (\sqrt{I_{0}} + \sqrt{I_{0}}) = {(2 \sqrt{I_{0}})}^{2} = 4 I_{0}$

$I = I_{\max} \cos^{2} (\frac{Δ ϕ}{2})$

$\cos^{2} (\frac{Δ ϕ}{2}) = \frac{1}{\sqrt{2}}$

$\frac{Δ ϕ}{2} = \frac{π}{4} or - \frac{π}{4} \Rightarrow Δ ϕ = \frac{π}{2} or - \frac{π}{2}$

$\frac{2 π}{λ} \times Δ x = Δ ϕ$

$\frac{2 π}{λ} \times Δ x = \frac{π}{2} \Rightarrow Δ x = \frac{λ}{4}$

From (i): $Δ x \approx d \tan θ, Δ x \approx \frac{d y}{D}$

$\frac{λ}{4} = \frac{d y}{D} \Rightarrow y = \frac{λ D}{4 d}$

$y = \frac{(5000 \times 10^{- 10}) (1)}{4 \times 10^{- 3}} = \frac{500}{4} \times 10^{- 6} = 125 \times 10^{- 6}$

Q 10 :

The width of one of the two slits in Young's double slit experiment is d while that of the other slit is xd. If the ratio of the maximum to the minimum intensity in the interference pattern on the screen is 9 : 4 then what is the value of x?

(Assume that the field strength varies according to the slit width.) [2025]

2
3
5
4

1

2

3

4

(3)

${(\frac{\sqrt{I_{1}} + \sqrt{I_{2}}}{\sqrt{I_{1}} - \sqrt{I_{2}}})}^{2} = \frac{9}{4}$

$\Rightarrow \frac{\sqrt{I_{1}} + \sqrt{I_{2}}}{\sqrt{I_{1}} - \sqrt{I_{2}}} = \frac{3}{2}$

$\frac{(x + 1) d}{(x - 1) d} = \frac{3}{2}$

$\Rightarrow 3 x - 3 = 2 x + 2 \Rightarrow x = 5$

Q 11 :

Given below are two statements. One is labelled as Assertion (A) and the other is labelled as Reason (R)

Assertion (A) : In Young's double slit experiment, the fringes produced by red light are closer as compared to those produced by blue light.

Reason (R) : The fringe width is directly proportional to the wavelength of light.

In the light of above statements, choose the correct answer from the options given below: [2025]

Both (A) and (R) are true and (R) is the correct explanation of (A).
(A) is false but (R) is true.
Both (A) and (R) are true but (R) is NOT the correct explanation of (A)
(A) is true but (R) is false.

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(2)

$β = \frac{λ D}{d}$

$λ_{red} < λ_{blue}$

Assertion is false

Reason is true

Q 12 :

Given below are two statements: One is labelled as Assertion (A) and the other is labelled as Reason (R)

Assertion (A) : If Young's double slit experiment is performed in an optically denser medium than air, then the consecutive fringes come closer.

Reason (R) : The speed of light reduces in an optically denser medium than air while its frequency does not change.

In the light of the above statements, choose the most appropriate answer from the options given below: [2025]

Both (A) and (R) are true and (R) is the correct explanation of (A)
(A) is false but (R) is true.
Both (A) and (R) are true but (R) is NOT the correct explanation of (A)
(A) is true but (R) is false.

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(1)

Fringe with $β = \frac{λ D}{d}$

Also, $v = \frac{c}{μ}$ frequency remains same

$\Rightarrow λ_{med} = \frac{λ_{vac}}{μ}$

Hence, $β$ decreases $\Rightarrow$ fringe come closer

Q 13 :

The Young's double slit interference experiment is performed using light consisting of 480 nm and 600 nm wavelengths to form interference patterns. The least number of the bright fringes of 480 nm light that are required for the first coincidence with the bright fringes formed by 600 nm light is [2025]

4
8
6
5

1

2

3

4

(4)

Fringe width of $λ_{1}$ = 480 nm

$β_{1} = \frac{λ_{1} D}{d} = 480 (\frac{D}{d})$

Similarly fringe width for $λ_{2}$ = 600 nm

$β_{2} = λ_{2} (\frac{D}{d}) = 600 (\frac{D}{d})$

Clearly we can see that for minimum value

$5 (β_{1}) = 4 (β_{2})$

That means $5^{th}$ maxima of $λ_{1}$ = 480 nm

coincides with $4^{th}$ maxima of $λ_{2}$ = 600 nm

Q 14 :

Young's double slit interference apparatus is immersed in a liquid of refractive index 1.44. It has slit separation of 1.5 mm. The slits are illuminated by a parallel beam of light whose wavelength in air in 690 nm. The fringe-width on a screen placed behind the plane of slits at a distance of 0.72 m, will be: [2025]

0.23 mm
0.33 mm
0.63 mm
0.46 mm

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2

3

4

(1)

$β = (\frac{λ_{0}}{μ}) \times \frac{D}{d} = \frac{690 \times 10^{- 9} \times 0.72}{1.44 \times 1.5 \times 10^{- 3}} = 0.23 mm$

Q 15 :

In a Young's double slit experiment, the slits are separated by 0.2 mm. If the slits separation is increased to 0.4 mm, the percentage change of the fringe width is: [2025]

0%
100%
50%
25%

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2

3

4

(3)

$β_{1} = \frac{λ D}{d}$

$β_{2} = \frac{λ D}{2 d} = \frac{β_{1}}{2}$

%change = 50%

Q 16 :

In a Young's double slit experiment, the source is white light. One of the slits is covered by red filter and another by a green filter. In this case [2025]

There shall be an interference pattern for red distinct from that for green.
There shall be no interference fringes.
There shall be alternate interference fringes of red and green.
There shall be an interference pattern, where each fringe's pattern center is green and outer edges is red.

1

2

3

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(2)

Q 17 :

A double slit interference experiment performed with a light of wavelength 600 nm forms an interference fringe pattern on a screen with 10th bright fringe having its centre at a distance of 10 mm from the central maximum. Distance of the centre of the same 10th bright fringe from the central maximum when the source of light is replaced by another source of wavelength 660 nm would be ________ mm. [2025]

(11)

In case of YDSE the distance of $n^{th}$ maxima from central maxima is given by

$y = \frac{n λ D}{d}$

Here n, D and d are same,

$\Rightarrow \frac{y_{10}^{'}}{y_{10}} = \frac{λ'}{λ}$

or $y_{10}^{'} = \frac{λ'}{λ} y_{10} = (\frac{660 nm}{600 nm}) 10 mm = 11 mm$

Q 18 :

In a Young's double slit experiment, two slits are located 1.5 mm apart. The distance of screen from slits is 2 m and the wavelength of the source is 400 nm. If the 20 maxima of the double slit pattern are contained within the centre maximum of the single slit diffraction pattern, then the width of each slit is $x \times 10^{- 3}$ cm, where x-value is ________. [2025]

(15)

$\frac{20 λ D}{d} = \frac{2 λ D}{a} \Rightarrow \frac{10}{d} = \frac{1}{a}$

$\Rightarrow a = \frac{d}{10} = \frac{1.5 \times 10^{- 1}}{10} cm = 15 \times 10^{- 3} cm$

Value of x is 15.

Q 19 :

In Young’s double slits experiment, the position of 5th bright fringe from the central maximum is 5 cm. The distance between slits and screen is 1 m and wavelength of used monochromatic light is 600 nm. The separation between the slits is [2023]

12 μm
60 μm
36 μm
48 μm

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3

4

(2)

$Position of 5th bright, \frac{5 D λ}{d} = 5 \times 10^{- 2} m$

$λ = 600 \times 10^{- 9} m = 6 \times 10^{- 7} m$

$D = 1 m, d = ?$

$d = 60 μ m$

Q 20 :

In a Young's double slit experiment, two slits are illuminated with a light of wavelength 800 nm. The line joining $A_{1} P$ is perpendicular to $A_{1} A_{2}$ as shown in the figure. If the first minimum is detected at $P$ , the value of slit separation ' $a$ ' will be

The distance of screen from slits D = 5 cm [2023]

0.4 mm
0.5 mm
0.2 mm
0.1 mm

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2

3

4

(3)

$A_{2} P - A_{1} P = \frac{λ}{2} (Condition of minima)$

$\sqrt{D^{2} + a^{2}} - D = \frac{λ}{2}$

$D {(1 + \frac{a^{2}}{D^{2}})}^{1 / 2} - D = \frac{λ}{2}$

$D (1 + \frac{1}{2} \times \frac{a^{2}}{D^{2}}) - D = \frac{λ}{2}$

$\frac{a^{2}}{2 D} = \frac{λ}{2} \Rightarrow a = \sqrt{λ D} = \sqrt{800 \times 10^{- 6} \times 50}$

$\Rightarrow a = 0.2 mm$

Q 21 :

The width of fringe is 2 mm on the screen in a double slits experiment for the light of wavelength of 400 nm. The width of the fringe for the light of wavelength 600 nm will be ________ [2023]

4 mm
1.33 mm
2 mm
3 mm

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2

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(4)

$Fringe width (β) = \frac{D λ}{d}$

$\Rightarrow \frac{β_{2}}{β_{1}} = \frac{λ_{2}}{λ_{1}}$

$\Rightarrow \frac{β_{2}}{2 mm} = \frac{600 nm}{400 nm} = \frac{3}{2}$

$\Rightarrow β_{2} = 3 mm$

Q 22 :

In Young's double slit experiment, two slits $S_{1}$ and $S_{2}$ are $' d'$ distance apart and the separation from slits to screen is $D$ (as shown in figure). Now if two transparent slabs of equal thickness 0.1 mm but refractive index 1.51 and 1.55 are introduced in the path of beam $(λ = 4000 Å)$ from $S_{1}$ and $S_{2}$ respectively. The central bright fringe spot will shift by _______ number of fringes. [2023]

(10)

$Path difference at P be Δ x$

$Δ x = (μ_{2} - μ_{1}) t = (1.55 - 1.51) 0.1 mm = 0.04 \times 10^{- 4}$

$Δ x = 4 \times 10^{- 6} = 4 μ m$

$y = \frac{Δ x D}{d} = 4 \times 10^{- 6} \frac{D}{d}$

$[y is the distance of central maxima from geometric center]$

$Fringe width = \frac{λ D}{d} = 4 \times 10^{- 6} m \frac{D}{d} = 4 μ m \frac{D}{d}$

$∴$ $Central bright fringe spot will shift by' x'$

$Number of shift = \frac{y}{β} = \frac{4 \times 10^{- 6} D / d}{4 \times 10^{- 7} D / d} = 10$

Q 23 :

In a Young's double slit experiment, the intensities at two points, for the path difference $\frac{λ}{4}$ and $\frac{λ}{3}$ ( $λ$ being the wavelength of light used) are $I_{1}$ and $I_{2}$ respectively. If $I_{0}$ denotes the intensity produced by each one of the individual slits, then $\frac{I_{1} + I_{2}}{I_{0}} =$ ________ . [2023]

(3)

$I = 4 I_{0} \cos^{2} (\frac{Δ ϕ}{2})$

$I_{1} = 4 I_{0} \cos^{2} (\frac{π}{4}) = 2 I_{0}$

$I_{2} = 4 I_{0} \cos^{2} (\frac{2 π}{3}) = I_{0}$

$\Rightarrow \frac{I_{1} + I_{2}}{I_{0}} = 3$

Q 24 :

Two light waves of wavelengths 800 and 600 nm are used in Young’s double slit experiment to obtain interference fringes on a screen placed 7 m away from plane of slits. If the two slits are separated by 0.35 mm, then shortest distance from the central bright maximum to the point where the bright fringes of the two wavelength coincide will be ________ mm. [2023]

(48)

$ω_{1} = \frac{λ_{1} D}{d} and ω_{2} = \frac{λ_{2} D}{d}$

$ω_{1} = 16 mm and ω_{2} = 12 mm$

$so LCM (ω_{1}, ω_{2}) = 48 mm$

$so at 48 mm distance both bright fringes will be found.$

Q 25 :

As shown in the figure, in Young's double slit experiment, a thin plate of thickness $t = 10 μ m$ and refractive index $μ = 1.2$ is inserted infront of slit $S_{1}$ . The experiment is conducted in air ( $μ = 1$ ) and uses a monochromatic light of wavelength $λ = 500 nm$ . Due to the insertion of the plate, central maxima is shifted by a distance of $x β_{0}$ . $β_{0}$ is the fringe-width before the insertion of the plate. The value of the $x$ is ________ . [2023]

(4)

$Fringe shift S = \frac{t (μ - 1)}{λ} β_{0}$

$= \frac{10 \times 10^{- 6} (1.2 - 1)}{5 \times 10^{- 7}} β_{0} = x β_{0}$

$\Rightarrow x = \frac{10^{- 5} \times 0.2}{5 \times 10^{- 7}} = 4$

Q 26 :

A beam of light consisting of two wavelengths 7000 $Å$ and 5500 $Å$ is used to obtain interference pattern in Young's double slit experiment. The distance between the slits is 2.5 mm and the distance between the plane of slits and the screen is 150 cm. The least distance from the central fringe, where the bright fringes due to both the wavelengths coincide, is $n \times 10^{- 5} m$ . The value of $n$ is _______. [2023]

(462)

$d = 2.5 mm, D = 150 cm$

$Fringe width β = \frac{λ D}{d}$

$Let n^{th} bright fringe of λ_{1} match with m^{th} bright fringe of λ_{2}$

$\Rightarrow n β_{1} = m β_{2}$

$\Rightarrow n λ_{1} = m λ_{2} \Rightarrow \frac{n}{m} = \frac{λ_{2}}{λ_{1}} = \frac{5500}{7000}$

$\Rightarrow \frac{n}{m} = \frac{11}{14}$

$Distance where bright fringe will match$

$= n β_{1} = \frac{11 \times 7000 Å \times 150 cm}{0.25 cm} = 462 \times 10^{- 5}$

Q 27 :

In two separate Young’s double-slit experimental set-ups, two monochromatic light sources of different wavelengths are used to get fringes of equal width. The ratios of the slit separations and that of the wavelengths of light used are 2 : 1 and 1 : 2 respectively. The corresponding ratio of the distances between the slits and the respective screens $(D_{1} / D_{2})$ is __________ . [2026]

(4)

$β_{1} = β_{2}$

$\frac{D_{1} λ_{1}}{d_{1}} = \frac{D_{2} λ_{2}}{d_{2}}$

$\frac{D_{1}}{D_{2}} = \frac{λ_{2}}{λ_{1}} (\frac{d_{1}}{d_{2}})$

$= 2 \times 2$

$\frac{D_{1}}{D_{2}} = 4$

Q 28 :

In a double slit experiment the distance between the slits is 0.1 cm and the screen is placed at 50 cm from the slits plane. When one slit is covered with a transparent sheet having thickness t and refractive index n (= 1.5), the central fringe shifts by 0.2 cm. The value of t is __________ cm. [2026]

$6.0 \times 10^{- 3}$
$5.6 \times 10^{- 4}$
$8 \times 10^{- 4}$
$8 \times 10^{- 4}$

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2

3

4

(3)

$d \sin θ = (μ - 1) t$

$d [\frac{x}{D}] = (μ - 1) t$

$t = \frac{x d}{D (μ - 1)}$

$= \frac{(0.2) (0.1)}{50 (1.5 - 1)}$

$t = 8 \times 10^{- 4} cm$

Q 29 :

A beam of light consisting of wavelengths 650 nm and 550 nm illuminates the Young’s double slits with separation of 2 mm such that the interference fringes are formed on a screen, placed at a distance of 1.2 m from the slits. The least distance of a point from the central maximum, where the bright fringes due to both the wavelengths coincide, is ________ $\times 10^{- 5}$ m. [2026]

(429)

$y = n \frac{λ D}{d}$

$y_{1} = y_{2}$

$n_{1} λ_{1} \frac{D}{d} = n_{2} λ_{2} \frac{D}{d}$

$\frac{n_{1}}{n_{2}} = \frac{λ_{2}}{λ_{1}} = \frac{550}{650} = \frac{11}{13}$

$y = 11 \times \frac{λ_{1} D}{d} = \frac{11 \times 650 \times 10^{- 9} \times 1.2}{2 \times 10^{- 3}}$

$y = 429 \times 10^{- 5}$

Q 30 :

In the Young's double slit experiment the intensity produced by each one of the individual slits is $I_{o}$ . The distance between two slits is 2 mm. The distance of screen from slits is 10 m. The wavelength of light is $6000$ $Å$ . The intensity of light on the screen in front of one of the slits is _________ . [2026]

$4 I_{o}$
$\frac{I_{o}}{2}$
$2 I_{o}$
$I_{o}$

1

2

3

4

(4)

$d = 2 mm$

$D = 10 m$

$λ = 6000 Å$

$y = \frac{d}{2} (in front of one slit)$

$I = 4 I_{0} \cos^{2} (\frac{2 π}{λ} \cdot \frac{y}{D} \cdot d)$

$\Rightarrow I = I_{0}$

Topic Question Set

Q 1 :

The width of one of the two slits in a Young’s double slit experiment is 4 times that of the other slit. The ratio of the maximum to the minimum intensity in the interference pattern is [2024]

Q 3 :

Two wavelengths $λ_{1}$ and $λ_{2}$ are used in Young's double slit experiment. $λ_{1}$ = 450 nm and $λ_{2}$ = 650 nm. The minimum order of fringe produced by $λ_{2}$ which overlaps with the fringe produced by $λ_{1}$ is $n$ . The value of $n$ is ____. [2024]

Q 4 :

In Young’s double slit experiment, carried out with light of wavelength 5000 $Å$ , the distance between the slits is 0.3 mm and the screen is at 200 cm from the slits. The central maximum is at $x$ = 0 cm. The value of $x$ for the third maxima is __________ mm. [2024]

Q 5 :

Two slits are 1 mm apart and the screen is located 1 m away from the slits. A light of wavelength 500 nm is used. The width of each slit to obtain 10 maxima of the double slit pattern within the central maximum of the single slit pattern is ___ × $10^{- 4}$ m. [2024]

Q 6 :

In a Young’s double slit experiment, the intensity at a point is ${(\frac{1}{4})}^{t h}$ of the maximum intensity. The minimum distance of the point from the central maximum is _____ µm.

(Given: $λ = 600 n m,$ $d = 1.0 m m,$ $D = 1.0 m$ ) [2024]

Q 8 :

In a double slit experiment shown in figure, when light of wavelength 400 nm is used, dark fringe is observed at P. If D = 0.2 m the minimum distance between the slits $S_{1}$ and $S_{2}$ is ____ mm. [2024]

Q 15 :

In a Young's double slit experiment, the slits are separated by 0.2 mm. If the slits separation is increased to 0.4 mm, the percentage change of the fringe width is: [2025]

Q 16 :

In a Young's double slit experiment, the source is white light. One of the slits is covered by red filter and another by a green filter. In this case [2025]

Q 19 :

In Young’s double slits experiment, the position of 5th bright fringe from the central maximum is 5 cm. The distance between slits and screen is 1 m and wavelength of used monochromatic light is 600 nm. The separation between the slits is [2023]

Q 21 :

The width of fringe is 2 mm on the screen in a double slits experiment for the light of wavelength of 400 nm. The width of the fringe for the light of wavelength 600 nm will be ________ [2023]

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Topic Question Set

Q 1 : The width of one of the two slits in a Young’s double slit experiment is 4 times that of the other slit. The ratio of the maximum to the minimum intensity in the interference pattern is [2024]

Q 3 : Two wavelengths λ1 and λ2 are used in Young's double slit experiment. λ1 = 450 nm and λ2 = 650 nm. The minimum order of fringe produced by λ2 which overlaps with the fringe produced by λ1 is n. The value of n is ____. [2024]

Q 4 : In Young’s double slit experiment, carried out with light of wavelength 5000 Å, the distance between the slits is 0.3 mm and the screen is at 200 cm from the slits. The central maximum is at x = 0 cm. The value of x for the third maxima is __________ mm. [2024]

Q 5 : Two slits are 1 mm apart and the screen is located 1 m away from the slits. A light of wavelength 500 nm is used. The width of each slit to obtain 10 maxima of the double slit pattern within the central maximum of the single slit pattern is ___ × 10-4 m. [2024]

Q 6 : In a Young’s double slit experiment, the intensity at a point is (14)thof the maximum intensity. The minimum distance of the point from the central maximum is _____ µm. (Given: λ=600nm, d=1.0mm, D=1.0m) [2024]

Q 8 : In a double slit experiment shown in figure, when light of wavelength 400 nm is used, dark fringe is observed at P. If D = 0.2 m the minimum distance between the slits S1 and S2 is ____ mm. [2024]

Q 15 : In a Young's double slit experiment, the slits are separated by 0.2 mm. If the slits separation is increased to 0.4 mm, the percentage change of the fringe width is: [2025]

Q 16 : In a Young's double slit experiment, the source is white light. One of the slits is covered by red filter and another by a green filter. In this case [2025]

Q 19 : In Young’s double slits experiment, the position of 5th bright fringe from the central maximum is 5 cm. The distance between slits and screen is 1 m and wavelength of used monochromatic light is 600 nm. The separation between the slits is [2023]

Q 21 : The width of fringe is 2 mm on the screen in a double slits experiment for the light of wavelength of 400 nm. The width of the fringe for the light of wavelength 600 nm will be ________ [2023]

Q 23 : In a Young's double slit experiment, the intensities at two points, for the path difference λ4 and λ3 (λ being the wavelength of light used) are I1 and I2 respectively. If I0 denotes the intensity produced by each one of the individual slits, then I1+I2I0= ________ . [2023]

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Q 1 :

The width of one of the two slits in a Young’s double slit experiment is 4 times that of the other slit. The ratio of the maximum to the minimum intensity in the interference pattern is [2024]

Q 3 :

Two wavelengths $λ_{1}$ and $λ_{2}$ are used in Young's double slit experiment. $λ_{1}$ = 450 nm and $λ_{2}$ = 650 nm. The minimum order of fringe produced by $λ_{2}$ which overlaps with the fringe produced by $λ_{1}$ is $n$ . The value of $n$ is ____. [2024]

Q 4 :

In Young’s double slit experiment, carried out with light of wavelength 5000 $Å$ , the distance between the slits is 0.3 mm and the screen is at 200 cm from the slits. The central maximum is at $x$ = 0 cm. The value of $x$ for the third maxima is __________ mm. [2024]

Q 5 :

Two slits are 1 mm apart and the screen is located 1 m away from the slits. A light of wavelength 500 nm is used. The width of each slit to obtain 10 maxima of the double slit pattern within the central maximum of the single slit pattern is ___ × $10^{- 4}$ m. [2024]

Q 6 :

In a Young’s double slit experiment, the intensity at a point is ${(\frac{1}{4})}^{t h}$ of the maximum intensity. The minimum distance of the point from the central maximum is _____ µm.

(Given: $λ = 600 n m,$ $d = 1.0 m m,$ $D = 1.0 m$ ) [2024]

Q 8 :

In a double slit experiment shown in figure, when light of wavelength 400 nm is used, dark fringe is observed at P. If D = 0.2 m the minimum distance between the slits $S_{1}$ and $S_{2}$ is ____ mm. [2024]

Q 15 :

In a Young's double slit experiment, the slits are separated by 0.2 mm. If the slits separation is increased to 0.4 mm, the percentage change of the fringe width is: [2025]

Q 16 :

In a Young's double slit experiment, the source is white light. One of the slits is covered by red filter and another by a green filter. In this case [2025]

Q 19 :

In Young’s double slits experiment, the position of 5th bright fringe from the central maximum is 5 cm. The distance between slits and screen is 1 m and wavelength of used monochromatic light is 600 nm. The separation between the slits is [2023]

Q 21 :

The width of fringe is 2 mm on the screen in a double slits experiment for the light of wavelength of 400 nm. The width of the fringe for the light of wavelength 600 nm will be ________ [2023]