List of top Physics Questions on Wave optics

In a YDSE set up, a slab of width \( t \) is inserted in front of one slit. The interference pattern shifts by 0.2 cm on the screen. If the refractive index of the slab is 1.5, then \( t \) in \( \mu m \) (screen distance 50 cm and slits separation 1 mm) then \( N \) is ..............
A polaroid \(P\) is placed between two crossed polaroids \(Q\) and \(R\) such that when unpolarised light is incident on \(Q\), it emerges from \(R\) with maximum possible intensity. The ratio of intensity of unpolarized light incident on \(P\) and the intensity of polarized light emerging from \(R\) is
Speed of Light in vacuum is :
What is the law of Malus? A plane polarized light of intensity 16 watt/m², is incident on a polaroid in such a way that the vibration of its electric vector makes an angle of 30° from the transmission axis of the polaroid. Find out the intensity of the transmitted light from the polaroid. Write down any one use of polaroid.
A thin transparent sheet is placed in front of one slit of a Young's double slit. The fringe width will:

What is the meaning of wavefront? Explain the laws of reflection on the basis of Huygens' principle of wavefront.
OR
Determine the following for the given A.C. circuit: (i) impedance, (ii) power factor, and (iii) phase difference between voltage and current. (Series combination of resistance \( R = 500\ \Omega \), inductance \( L = 10\ \text{H} \) and capacitance \( C = 20\ \mu\text{F} \) connected to an A.C. source \( V = 200\sin 100t \).)
Write Huygen's principle of secondary wavelets and verify laws of refraction on its basis.
OR
Explain the meaning of coherent sources and sustained interference. Why central fringe in Young's double slit experiment is always bright? In Young's double slit experiment, fringe width is 0.04 cm for light of 6000 Å. Distance of screen from slits is 1 m. Find the distance of third bright and second dark fringe from central fringe and also the separation between the slits.
Write formula for the position of minima in the diffraction pattern of a single slit.
A concave mirror is used to form an image of an object. The object distance (u) is 30 cm and the image distance (v) is 15 cm. Calculate the focal length (f) of the mirror.
The objective of a microscope is immersed in a liquid of refractive index 1.5. If the semi-vertical angle of the cone of light rays of wavelength 600 nm from the object that fall on the objective is \(30^\circ\), then the minimum resolvable distance for this microscope is:
In YDSE, intensity at path difference $\lambda/3$ is I. Find intensity at path difference $\lambda$.
In Young's double slit experiment, when a screen is placed at a distance of 1.2 m from the plane of the slits, the fringe width is 2 mm. If the setup is immersed in a liquid of refractive index 1.25 and the screen is moved to a distance of 1.8 m from the slits, then the fringe width is
Two coherent monochromatic light beams of intensities \(I\) and \(4I\) are superposed. What are the maximum and minimum possible intensities in the resulting beam?
If a parallel beam of light of wavelength $500\text{ nm}$ is incident on a convex lens of focal length $20\text{ cm}$ having a circular aperture of diameter $5\text{ cm}$, then the radius of the central bright diffraction spot formed on the focal plane of the lens is nearly (in $\mu\text{m}$):
The length of an open pipe is half of the length of another closed pipe. When the two pipes are vibrated, four nodes are formed in both the cases. The ratio of the frequencies of the open and the closed pipes is:
In Young's double slit experiment, if the light of wavelength \(6000\AA\) is used, the fringe width is \(\beta\). If \(I\) is the intensity of light at a point on the screen where the path difference becomes \(2000\AA\), then the intensity of light at a point on the screen which is located at a distance of \(\frac{\beta}{6}\) from the central maximum is:
Beyond what distance, the ray optics is sufficiently valid when the aperture is 6 mm wide and the wavelength is 6000 \AA?
If two waves of same wavelength with their intensities in the ratio $25:9$ produce interference, then the ratio of the maximum to minimum intensity is
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.
A point source is kept at centre of a sphere. The intensity of light at point \(A\) is \(I\). Find intensity at point \(B\).
Unpolarised light with intensity \(I_0\) is incident on a polariser. Find angle between axis of polariser and analyser such that intensity of emergent light becomes \( \frac{3I_0}{8} \).
Intensity of two sources is same and path difference at point \(A\) and \(B\) are \( \frac{\lambda}{6} \) and \( \frac{\lambda}{3} \) respectively. Ratio of intensity at \(A\) and \(B\) will be.
In YDSE a glass slab of thickness \(8\,\mu m\) is introduced in front of a slit. If central maxima shifts to the position of 4th minima, then find refractive index of glass slab \((\lambda = 500\,\text{nm})\):
Find transverse magnification due to curved boundary between two mediums as shown in the figure. Refractive index of second medium \(n_2 = 1.4\).
In a Young's double slit experiment, the slits are separated by 0.2 mm and placed 2.0 m away. The distance between the central bright fringe and the first bright fringe (fringe width) is measured to be 1.5 cm. Determine the wavelength of light used in the experiment.