Wave Optics — JEE Main PYQs

In a Young's double slit experiment two slits are separated by 2 mm and the screen is placed one meter away. When a light of wavelength 500 nm used, the fringe separation will be :

In a Young's double slit experiment, the slits are separated by 0.3 mm and the screen is 1.5 m away from the plane of slits. Distance between fourth bright fringes on both sides of central bright is 2.4 cm. The frequency of light used is ______ $\times 10^{14}\mathrm{Hz}$.

In Young's double slit experiment, if the source of light changes from orange to blue then:

In the Young's double slit experiment, the distance between the slits varies in time as $d(t)=d_0+a_0\sin \omega t$; where $d_0,\omega$ and $a_0$ are constants. The difference between the largest fringe width and the smallest fringe width obtained over time is given as …

The difference in the number of waves when yellow light propagates through air and vacuum columns of the same thickness is one. The thickness of the air column is ____ mm .
[Refractive index of air $=1.0003$, wavelength of yellow light in vacuum $=6000\mathring{A}$ ]

The width of one of the two slits in a Young's double slit experiment is three times the other slit. If the amplitude of light coming from a slit is proportional to the slit-width, the ratio of minimum to maximum intensity in the interference pattern is $\mathrm{x}:4$ where x is …

A fringe width of 6 mm was produced for two slits separated by 1 mm apart. The screen is placed 10 m away. The wavelength of light used is ' x ' nm .
The value of ' $x$ ' to the nearest integer is ____

In Young's double slit arrangement, slits are separated by a gap of 0.5 mm, and the screen is placed at a distance of 0.5 m from them. The distance between the first and the third bright fringe formed when the slits are illuminated by a monochromatic light of $5890\mathring{A}$ is:

A polarizer-analyser set is adjusted such that the intensity of light coming out of the analyser is just 10% of the original intensity. Assuming that the polarizer-analyser set does not absorb any light, the angle by which the analyser need to be rotated further to reduce the out …

Visible light of wavelength $6000\times 10^{-8}$ cm falls normally on a single slit and produces a diffraction pattern. It is found that the second diffraction minimum is at $60^{\circ }$ from the central maximum. If the first minimum is produced at ${\theta }_1$ then ${\theta }_1$ …

In a Young's double slit experiment, the separation between the slits is 0.15 mm. In the experiment, a source of light of wavelength 589 nm is used and the interference pattern is observed on a screen kept 1.5 m away. The separation between the successive bright fringes on the sc …

In a double-slit experiment, at a certain point on the screen the path difference between the two interfering waves is $\frac{1}{8}$ th of a wavelength. The ratio of the intensity of light at that point to that at the centre of a bright fringe is:

In a Young's double slit experiment 15 fringes are observed on a small portion of the screen when light of wavelength 500 nm is used. Ten fringes are observed on the same section of the screen when another light source of wavelength $\lambda$ is used. Then the value of $\lambda$ …

The aperture diameter of a telescope is 5 m. The separation between the moon and the earth is $4\times 10^5\text{ km}$. With light of wavelength of 5500 Å, the minimum separation between objects on the surface of moon, so that they are just resolved, is close to:

In a Young's double slit experiment, light of 500 nm is used to produce an interference pattern. When the distance between the slits is 0.05 mm, the angular width (in degree) of the fringes formed on the distance screen is close to:

Two light waves having the same wavelength $\lambda$ in vacuum are in phase initially. Then the first wave travels path $L_1$ through a medium of refractive index $n_1$ while the second wave travels a path of length $L_2$ through a medium of refractive index $n_2$. After …

A Young's double-slit experiment is performed using monochromatic light of wavelength $\lambda$. The intensity of light at a point on the screen, where the path difference is $\lambda$, is K units. The intensity of the light at a point where the path difference is …

In the figure below, P and Q are two equally intense coherent sources emitting radiation of wavelength 20 m. The separation between P and Q is 5 m and the phase of P is ahead of that of Q by $90^{\circ }$. A, B and C are three distinct points of observation, each equidistant from …

A beam of plane polarized light of large cross-sectional area and uniform intensity of $3.3{\mathrm{Wm}}^{-2}$ falls normally on a polarizer (cross sectional area $3\times 10^{-4}{\mathrm{m}}^2$ ) which rotates about its axis with an angular speed of …

Orange light of wavelength $6000\times 10^{-10}\mathrm{m}$ illuminates a single slit of width $0.6\times 10^{-4}\mathrm{m}$. the maximum possible number of diffraction minima produced on both sides of the central maximum is ____

In an interference experiment the ratio of amplitudes of coherent waves is $\frac{{\mathrm{a}}_1}{{\mathrm{a}}_2}=\frac{1}{3}$. The ratio of maximum and minimum intensities of fringes will be:

In a Young's double slit experiment with slit separation 0.1 mm, one observes a bright fringe at angle $\frac{1}{40}\mathrm{rad}$ by using light of wavelength ${\lambda }_1$. When the light of wavelength ${\lambda }_2$ is used a bright fringe is seen at the same angle in the …

In a double-slit experiment, green light (5303 Å) falls on a double slit having a separation of $19.44\mu \mathrm{m}$ and a width of $4.05\mu \mathrm{m}$. The number of bright fringes between the first and the second diffraction minima is:

The value of numerical aperature of the objective lens of a microscope is 1.25. If light of wavelength $5000\mathring{A}$ is used, the minimum separation between two points, to be seen as distinct, will be :

In a double slit experiment, when a thin film of thickness t having refractive index $\mu$ is introduced in front of one of the slits, the maximum at the centre of the fringe pattern shifts by one fringe width. The value of $t$ is ( $\lambda$ is the wavelength of the light …

In a Young's double slit experiment the ratio of the slit's width is $4:1$. The ratio of the intensity of maxima to minima, close to central fringe on the screen will be

In a Young's double slit experiment, the path difference, at a certain point on the screen, between two interfering waves is $1/8^{\text{th }}$ of wavelength. The ratio of the intensity at this point to that at the centre of a bright fringe is close to:

A system of three polarizers ${\mathrm{P}}_1,{\mathrm{P}}_2,{\mathrm{P}}_3$ is set up such that the pass axis of ${\mathrm{P}}_3$ is crossed with respect to that of ${\mathrm{P}}_1$. The pass axis of ${\mathrm{P}}_2$ is inclined at $60^{\circ }$ to the pass axis of …

Diameter of the objective lens of a telescope is 250 cm . For light of wavelength 600 nm . Coming from a distant object, the limit of resolution of the telescope is close to:-

In a Young's double slit experiment, the slits are placed 0.320 mm apart. Light of wavelength $\lambda =500\mathrm{nm}$ is incident on the slits. The total number of bright fringes that are observed in the angular range $-30^{\circ }\le \theta \le 30^{\circ }$ is:

Two coherent sources produce waves of different intensities which interfere. After interference, the ratio of the maximum intensity to the minimum intensity is 16. The intensity of the waves are in the ratio:

Consider a tank made of glass (refractive index 1.5) with a thick bottom. It is filled with a liquid of refractive index $\mu$. A student finds that, irrespective of what the incident angle I (see figure) is for a beam of light entering the liquid, the light reflected from the …

Unpolarized light of intensity I passes through an ideal polarizer A. Another identical polarizer B is placed behind A . The intensity of light beyond B is found to be $\frac{\mathrm{I}}{2}$. Now another identical polarizer C is placed between A and B. The intensity beyond B is …

The angular width of the central maximum in a single slit diffraction pattern is $60^{\circ }$. The width of the slit is $1\mu \mathrm{m}$. The slit is illuminated by monochromatic plane waves. If another slit of same width is made near it, Young's fringes can be observed on a sc …

In a Young's double slit experiment, slits are separated by 0.5 mm, and the screen is placed 150 cm away. A beam of light consisting of two wavelengths, 650 nm and 520 nm, is used to obtain interference fringes on the screen. The least distance from the common central maximum to …

The box of pin hole camera, of length L, has a hole of radius $a$. It is assumed that when the hole is illuminated by a parallel beam of light of wavelength $\lambda$ the spread of the spot (obtained on the opposite wall of the camera) is the sum of its geometrical spread and …

Assuming human pupil to have a radius of 0.25 cm and a comfortable viewing distance of 25 cm , the minimum separation between two objects that human eye can resolve at 500 nm wavelength is:

On a hot summer night, the refractive index of air is smallest near the ground and increases with height from the ground. When a light beam is directed horizontally, the Huygens' principle leads us to conclude that as it travels, the light beam:

Two beams, A and B, of plane polarized light with mutually perpendicular planes of polarization are seen through a polaroid. From the position when the beam A has maximum intensity (and beam B has zero intensity), a rotation of Polaroid through $30^0$ makes the two beams appear …

A beam of unpolarised light of intensity ${\mathrm{I}}_0$ is passed through a polaroid A and then through another polaroid B which is oriented so that its principal plane makes an angle of $45^{\circ }$ relative to that of A. The intensity of the emergent light is:

Two coherent point sources ${\mathrm{S}}_1$ and ${\mathrm{S}}_2$ are separated by a small distance 'd' as shown. The fringes obtained on the screen will be:

In Young's double slit experiment, one of the slit is wider than other, so that the amplitude of the light from one slit is double of that from other slit. If ${\mathrm{I}}_{\mathrm{m}}$ be the maximum intensity, the resultant intensity I when they interfere at phase difference …

Direction:

The question has a paragraph followed by two statements, Statement -1 and statement -2 . Of the given four alternatives after the statements, choose the one that describes the statements.
A thin air film is formed by putting the convex surface of a plane - convex lens …

As the beam enters the medium, it will

The initial shape of the wave front of the beam is

The speed of light in the medium is

A mixture of light, consisting of wavelength 590 nm and an unknown wavelength, illuminates Young's double slit and gives rise to two overlapping interference patterns on the screen. The central maximum of both lights coincide. Further, it is observed that the third bright fringe …

In an experiment, electrons are made to pass through a narrow slit of width 'd' comparable to their de Broglie wavelength. They are detected on a screen at a distance 'D' from the slit (see figure).

Which of the following graph can be expected to represent the number of electron …

In a Young's double slit experiment the intensity at a point where the path difference is $\frac{\lambda }{6}$ ($\lambda$ being the wavelength of the light used) is I. If ${\mathrm{I}}_0$ denotes the maximum intensity, $\frac{\mathrm{I}}{{\mathrm{I}}_0}$ is equal to

A Young's double slit experiment uses a monochromatic source. The shape of the interference fringes formed on a screen is