JEE Main Physics — Optics previous year questions with solutions.
Light of wavelength $550 \mathrm{~nm}$ falls normally on a slit of width $22.0 \times 10^{-5} \mathrm{~cm}$. The angular position of the second minima from the central maximum will be (in radians)
A planoconvex lens becomes an optical system of $28 \mathrm{~cm}$ focal length when its plane surface is silvered and illuminated from left to right as shown in Fig-A. If the same lens is instead silvered on the curved surface and illuminated from other side as in Fig. B, it acts like an optical system of focal length $10 \mathrm{~cm}$. The refractive index of the material of lens is 
A ray of light is incident at an angle of ${ 60}^{\circ }$ on one face of a prism of angle ${ 30}^{\circ }$. The emergent ray of light makes an angle of ${ 30}^{\circ }$ with incident ray. The angle made by the emergent ray with second face of prism will be:
Light of wavelength $550\mathrm{nm}$ falls normally on a slit of width $22.0\times {10}^{-5}\mathrm{cm}$. The angular position of the second minima from the central maximum will be (in radians):
The angular width of the central maximum in a single slit diffraction pattern is $60^{\circ}$ . The width of the slit is $1\mu m$. The slit is illuminated by monochromatic plane waves. If another slit of the same width is made near it, Young's fringes can be observed on a screen placed at a distance $50 \mathrm{cm}$ from the slits. If the observed fringe width is $1 \mathrm{cm}$, what is slit separation distance? (i.e., the distance between the centres of each slit.)
Unpolarized light of intensity $I$ passes through an ideal polariser $A$. Another identical polariser $B$ is placed behind $A$. The intensity of light beyond B is found to be $\frac{I}{2}$. Now another identical polariser $C$ is placed between $A$ and $B$. The intensity beyond B is now found to be $\frac{I}{8}$ . The angle between polariser $A$ and $C$ is
A plane polarized light is incident on a polariser with its pass axis making angle $\theta$ with $\mathrm{x}$-axis, as shown in the figure. At four different values of $\theta, \theta=8^{\circ}, 38^{\circ}, 188^{\circ}$ and $218^{\circ}$, the observed intensities are same. What is the angle between the direction of polarization and $\mathrm{x}$-axis 
A single slit of width $b$ is illuminated by a coherent monochromatic light of wavelength $\lambda .$ If the second and fourth minima in the diffraction pattern at a distance $1\mathrm{cm}$ from the slit are at $3\mathrm{cm}$ and $6\mathrm{cm}$ respectively from the central maximum, what is the width of the central maximum? (i.e. distance between first minimum on either side of the central maximum)
Let the refractive index of a denser medium with respect to rarer medium be ${n}_{12}$ and its critical angle be ${\theta }_{C}$ . At an angle of incidence $A$ when light is travelling from denser medium to rarer medium, a part of the light is reflected and the rest is refracted and the angle between reflected and refracted rays is ${90}^{o}$. Angle $A$ is given by
A single slit of width $0.1\mathrm{mm}$ is illuminated by a parallel beam of light of wavelength $6000 Å$ and diffraction bands are observed on a screen $0.5m$ from the slit. The distance of the third dark band from the central bright band is:
In a Young's double slit experiment, slits are separated by $0.5\mathrm{mm}$, and the screen is placed $150\mathrm{cm}$ away. A beam of light consisting of two wavelengths, $650\mathrm{nm}$ and $520\mathrm{nm}$, is used to obtain interference fringes on the screen. The least distance from the common central maximum to the point where the bright fringes due to both the wavelengths coincide is:
In an experiment a convex lens of focal length $15\mathrm{cm}$ is placed coaxially on an optical bench in front of a convex mirror at a distance of $5\mathrm{cm}$ from it. It is found that an object and its image coincide, if the object is placed at a distance of $20\mathrm{cm}$ from the lens. The focal length of the convex mirror is-
A diverging lens with magnitude of focal length $25\mathrm{cm}$ is placed at a distance of $15\mathrm{cm}$ from a converging lens of magnitude of focal length $20\mathrm{cm}$. A beam of parallel light falls on the diverging lens. The final image formed is:
To determine refractive index of glass slab using a travelling microscope, minimum number of readings required are :
An observer looks at a distant tree of height $10m$ with a telescope of magnifying power of $20$. To the observer, the tree appears as
A convex lens, of focal length 30 cm, a concave lens of focal length 120 cm, and a plane mirror are arranged as shown. For an object kept at a distance of 60 cm from the convex lens, the final image, formed by the combination, is a real image, at a distance of: 
Two stars are 10 light years away from the earth. They are seen through a telescope of objective diameter 30 cm. The wavelength of light is 600nm. To see the stars just resolved by the telescope, the minimum distance between them should be $(1 light year=9.46\times {10}^{15}m)$ of the order of :
In an experiment for determination of refractive index of glass of a prism by $i$ v/s $\delta$ plot, it was found that a ray incident at angle ${35}^{o}$ , suffers a deviation of ${40}^{o}$ and that it emerges at angle ${79}^{o}$ . In that case which of the following is closest to the maximum possible value of the refractive index?
The box of a 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 the spread due to diffraction. The spot would then have its minimum size (say ${b}_{min}$ ) when:
A hemispherical glass body of radius 10 cm and refractive index 1.5 is silvered on its curved surface. A small air bubble is 6 cm below the flat surface inside it along the axis. The position of the image of the air bubble made by the mirror is seen : 
To find the focal length of a convex mirror, a student records the following data:<table class="pyq-table"><tbody><tr><td>Object pin</td><td>Convex Lens</td><td>Convex Mirror</td><td>Image Pin</td></tr><tr><td>22.2 cm</td><td>32.2 cm</td><td>45.8 cm</td><td>71.2 cm</td></tr></tbody></table>The focal length of the convex lens is ${f}_{1}$ and that of mirror is ${f}_{2}$ . Then taking index correction to be negligibly small, ${f}_{1}$ and ${f}_{2}$ are close to:
In Young's double-slit experiment, the distance between slits and the screen is $1m$ and monochromatic light of wavelength $600\mathrm{nm}$ is being used. A person standing near the slits is looking at the fringe pattern. When the separation between the slits is varied, the interference pattern disappears for a particular distance ${d}_{0}$ between the slits. If the angular resolution of the eye is $\frac{1}{60}^{\circ}$, then the value of ${d}_{0}$ is close to
In a Young's double slit experiment with light of wavelength $\lambda ,$ the separation of slits is $d$ and distance of screen is $D$ such that $D\gg d\gg \lambda$ . If the Fringe width is $\beta$ , the distance from point of maximum intensity to the point where intensity falls to half of the maximum intensity on either side is:
Assuming that the human pupil has a radius of $0.25 \mathrm{cm}$ and a comfortable viewing distance of $25\mathrm{cm}$. The minimum separation between two point objects that the human eye can resolve for the light of wavelength $500\mathrm{nm}$ is