Wave optics practice · Mixed difficulty

The sky appears blue, because

In Young's double slit experiment if the separation between coherent sources is doubled and distance of screen from slit plane is halved, then fringe width becomes

${n^{th}}$ Bright fringe if red light $\left( {{\lambda _1} = 7500\mathop \mathrm{A}\limits^ \circ } \right)$ coincides with ${\left( {n + 1} \right)^{th}}$ bright fringe of green light $\left( {{\lambda _2} = 6000\mathop \mathrm{A}\limits^ \circ } \right)$. The value of $n = ?$

Wavefront of a wave has direction with wave motion

An optically active compound

${V_O}\;and\;{V_E}$ represent the velocities, ${\mu _O}\;and\;{\mu _E}$ the refractive indices of ordinary and extraordinary rays for a doubly refracting crystal. Then

In Young’s double slit experiment, distance between two slits is $0.28\;\mathrm{mm}$ and distance between slits and screen is $1.4\;\mathrm{m}$. Distance between central bright fringe and third bright fringe is $0.9\;\mathrm{cm}$, what is the wavelength of light used?

Plane polarised light is passed through a polaroid. On viewing through the polaroid we find that when the polariod is given one complete rotation about the direction of the light, one of the following is observed

In single slit diffraction pattern

Assertion : Polaroid glasses reduce glare from road or water etc.

Reason : Reflected waves are partially polarised.

Monochromatic light of wavelength $600 \mathrm{~nm}$ is incident from air on a glass surface (refractive index of glass is $1.5$). The frequency of the refracted light will be

Statement-1: In Young's double slit experiment the two slits are at distance $d$ apart. Interference pattern is observed on a screen at distance $D$ from the slits. At a point on the screen when it is directly opposite to one of the slits, a dark fringe is observed. Then the wavelength of wave is proportional to square of distance between the two slits.
Statement-2: For a dark fringe intensity is zero.

A ray of light falls on a transparent glass slab with refractive index (relative to air) of $\mathrm{1}\mathrm{.62}$. The angle of incidence for which the reflected and refracted rays are mutually perpendicular is

When both the components of electric field of light waves are present such that one is stronger than the other and such light is viewed through a rotating analyser, one sees a maximum and a minimum of intensity but not complete darkness. This kind of light is called

A parallel beam of monochromatic unpolarised
light is incident on a transparent plate of
refractive index $\sqrt{3}.$ The reflected beam is
completely polarized. The angle of incidence
is

Wavefront means

Two coherent light sources having intensity in the ratio $2\, \times$ produce an interference pattern. The ratio $\frac{{\begin{array}{cccccccccccccccccccc} {{l_{\max }} - }&{{l_{\min }}} \end{array}}}{{\begin{array}{cccccccccccccccccccc} {{l_{\max }} + }&{{l_{\min }}} \end{array}}}$ will be

In Young’s double slit experiment, when violet light of wavelength $4358\mathop \mathrm{A}\limits^ \circ$ is used, the 84 fringe are seen in the field of view, but when sodium light of certain wavelength is used, then 62 fringes are seen in the field of view, the wavelength of sodium light is

In Young's double slit experiment, slits are separated by $2 \mathrm{~mm}$ and the screen is placed at a distance of $1.2 \mathrm{~m}$ from the slits. Light consisting of two wavelengths $6500\,\,\mathop {\text{A}}\limits^ \circ$ and $5200\,\,\mathop {\text{A}}\limits^ \circ$ are used to obtain interference fringes. Then, the separation between the fourth bright fringes of two different patterns produced by the two wavelengths is

Oil floating on water looks coloured due to interference of light. What should be the order of magnitude of thickness of oil layer in order that this effect may be observed?

Assertion: Incoming light reflected by earth is partially polarized.
Reason: Atmospheric particle polarize the light.

A beam of natural light falls on a system of 6 polaroids, which are arranged in succession such that each polaroid is turned through ${30^\circ }$ with respct to the preceding one. The percentage of incident intensity that passes through the system will be

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

The ratio of the intensity at the centre of a bright fringe to the intensity at a point one-quarter of the distance between two fringe from the centre is

Light waves can be polarized as they are

Two parallel slits $0.6\,mm$ apart are illuminated by light source of wave length $6000\,\mathop \mathrm{A}\limits^ \circ$. The distance between two consecutive dark fringes on a screen $1\,\,m$ away from the slits is

Resolving power of microscope depends upon

Assertion: Distance between position of bright and dark fringe remain same in YDSE
Reason: Fringe width $\beta=\frac{\lambda D}{d}$

A beam of light consisting of two wavelengths $650\;nm$ and $520\;nm$ is used to illuminate the slit of a Young’s double slit experiment. Then the order of the bright fringe of the longer wavelength that coincide with a bright fringe of the shorter wavelength at the least distance from the central maximum is

Assertion: We cannot observe diffraction pattern from a wide slit iluminated by monochromatic light.

Reason: In diffraction pattern, all the bright bands are not of the same intensity.