Wave Optics · Physics · COMEDK
MCQ (Single Correct Answer)
If the intensity of the central maximum in the Young's double slit experiment is $\mathrm{I}_0$, what will be the intensity at the same region when one of the slits is blocked by an opaque object?
In a single slit diffraction experiment, the diffraction pattern is observed on a screen placed at a distance of 2 m from the slit of 1 mm width. If the distance between the first dark fringe on either side of the central to right fringe is 2.2 mm . what is the wave length of the monochromatic light from a distance source, used in this experiment?
The width of the fringes obtained with a light of wave length $6.2 \times 10^{-8} \mathrm{~m}$ is 1.82 mm . If the whole apparatus is immersed in a liquid of refractive index 1.3 , what will be the width of the resulting fringe?
A diffraction pattern due to a single slit of width 0.12 mm is obtained with a blue green light of wavelength 500 nm . The angular separation between central maximum and second order secondary maximum of the diffraction pattern is
In a Young's double slit experiment, the slit separation is 1.5 mm . The setup is illuminated simultaneously by light of wavelengths $6000 \mathop {\rm{A}}\limits^{\rm{o}}$ and $8000 \mathop {\rm{A}}\limits^{\rm{o}}$. The screen is placed at a distance of 1.5 m from the slits. It is observed that at a certain point $P$ on the screen which is 4.8 mm from the central maximum, fringes due to both the wavelengths coincide.
Which of the following options are correct?
A. Light of wavelength $6000\mathop {\rm{A}}\limits^{\rm{o}}$ produces a dark fringe and light of wavelength $8000 \mathop {\rm{A}}\limits^{\rm{o}}$ produces a bright fringe at P
B. Light of wavelength $6000 \mathop {\rm{A}}\limits^{\rm{o}}$ produces a bright fringe and light of wavelength $8000 \mathop {\rm{A}}\limits^{\rm{o}}$ produces a dark fringe at P
C. Light of wavelength $6000\mathop {\rm{A}}\limits^{\rm{o}}$ and light of wavelength $8000 \mathop {\rm{A}}\limits^{\rm{o}}$ both produce a dark fringe at P
D. Light of wavelength $6000 \mathop {\rm{A}}\limits^{\rm{o}}$ and light of wavelength $8000\mathop {\rm{A}}\limits^{\rm{o}}$ both produce a bright fringe at P
In a Young's double slit experiment, the slits are separated by 0.5 mm . Fringes are obtained on a screen which is placed at distance 1 m away from the slits. When the screen is moved 7 cm farther away, the fringe width changes by $63 \mu \mathrm{~m}$. The wavelength of light used in the experiment will be:
In Young's double slit experiment light of wavelength $$500 \mathrm{~nm}$$ is used to form interference pattern. A uniform glass plate of refractive index 1.5 and thickness $$0.1 \mathrm{~mm}$$ is introduced in the path of one of the interfering beams. The number of fringes that will shift due to this is
Two narrow parallel slits illuminated by a coherent monochromatic light produces an interference pattern on a screen placed at a distance $$\mathrm{D}$$ from the slits. The separation between the dark lines of the interference pattern can be increased by
A monochromatic light of wavelength $$800 \mathrm{~nm}$$ is incident normally on a single slit of width $$0.020 \mathrm{~mm}$$ to produce a diffraction pattern on a screen placed $$1 \mathrm{~m}$$ away. Estimate the number of fringes obtained in Young's double slit experiment with slit separation $$0.20 \mathrm{~mm}$$, which can be accommodated within the range of total angular spread of the central maximum due to single slit.
Incident light of wavelength $$\lambda=800 \mathrm{~nm}$$ produces a diffraction pattern on a screen $$1.5 \mathrm{~m}$$ away when it passes through a single slit of width $$0.5 \mathrm{~mm}$$. The distance between the first dark fringes on either side of the central bright fringe is
A slit of width $$10 \times 10^{-7} \mathrm{~m}$$ is illuminated by light of wavelength $$500 \mathrm{~nm}$$. Angular position of the first minimum is
In Young's double slit experiment the ratio of phase difference between light waves reaching the third bright fringe and third dark fringe is
In Young's double slit experiment, the ratio of intensities of light from one slit to the other is $$9: 1$$. If Im is the maximum intensity, what is the resultant intensity when they interfere at phase difference $$\phi$$ ?
In Young's double slit experiment, the intensity of light at a point on the screen where the path difference is $$\lambda$$ is $$\mathrm{K}$$ units ($$\lambda$$ is the wavelength of light used). The percentage change in intensity at a point where the path difference is $$\frac{\lambda}{6}$$ and the above point is
In the Young's double slit experiment $$n^{\text {th }}$$ bright for red coincides with $$(n+1)^{\text {th }}$$ bright for violet. Then the value of '$$n$$' is: (given: wave length of red light $$=6300^{\circ} \mathrm{A}$$ and wave length of violet $$=4200^{\circ} \mathrm{A}$$).
When light wave passes from a medium of refractive index '$$\mu$$' to another medium of refractive index '$$2 \mu$$' the phase change occurs to the light is :
The width of the fringes obtained in the Young's double slit experiment is $$2.6 \mathrm{~mm}$$ when light of wave length $$6000^{\circ} \mathrm{A}$$ is used. If the whole apparatus is immersed in a liquid of refractive index 1.3 the new fringe width will be :
In a single slit diffraction experiment, for slit width '$$\alpha$$' the width of the central maxima is '$$\beta$$'. If we double the slit width then the corresponding width of the central maxima will be:
In Young's double slit interference experiment, using two coherent waves of different amplitudes, the intensities ratio between bright and dark fringes is 3 . Then, the value of the ratio of the amplitudes of the wave that arrive there is
In Young's double slit experiment, the ratio of maximum and minimum intensities in the fringe system is $$9: 1$$. The ratio of amplitudes of coherent sources is
In the young's double slit experiment the fringe width of the interference pattern is found to be $$3.2 \times 10^{-4} \mathrm{~m}$$, when the light of wave length $$6400^{\circ} \mathrm{A}$$ is used. What will be change in fringe width if the light is replaced with a light of wave length $$4800^{\circ} \mathrm{A}$$
A light having wavelength $$6400^{\circ} \mathrm{A}$$ is incident normally on a slit of width $$2 \mathrm{~mm}$$. Then the linear width of the central maximum on the screen kept $$2 \mathrm{~m}$$ from the slit is :
In Young's double slit experiment, the two slits are separated by 0.2 mm and they are 1 m from the screen. The wavelength of the light used is 500 nm. The distance between 6th maxima and 10th minima on the screen is closest to
In Young's double slit experiment, the fringe width is found to be 0.4 mm. If the whole apparatus is immersed in a liquid of refractive index $$\frac{4}{3}$$ without changing geometrical arrangement, the new fringe width will be
An unpolarised beam of intensity I$$_0$$ is incident on a pair of nicols making an angle of 60$$^\circ$$ with each other. The intensity of light emerging from the pair is
In Young's double slit experiment with sodium vapour lamp of wavelength 589 nm and slit 0.589 mm apart, the half angular width of the central maxima is
Two identical light waves, propagating in the same direction, have a phase difference $$\delta$$. After they superpose the intensity of the resulting wave will be proportional to
A plastic sheet (refractive index = 1 6. ) covers one slit of a double slit arrangement for the Young’s experiment. When the double slit is illuminated by monochromatic light (wavelength = 5867 $$\mathop A\limits^o $$), the centre of the screen appears dark rather than bright. The minimum thickness of the plastic sheet to be used for this to happen is