YDSE Problems III

Q. Assume that light of wavelength $600\text{nm}$ is coming from a star. The limit of resolution of telescope whose objective has a diameter of $2\text{m}$ is

1. $7.32\times {10}^{-7}\text{rad}$
2. $6\times {10}^{-7}\text{rad}$
3. $3.66\times {10}^{-7}\text{rad}$
4. $1.83\times {10}^{-7}\text{rad}$

Q. In YDSE experiment if slit separation is 0.4 mm and wavelength of light used is 400 nm, then number of maxima observed [for $\theta ={37}^{\circ }$] between C and P are

1. 224
2. 749
3. 500
4. 598

Q. Two sources $S_1\text{and}{S}_2$ emitting light of wavelength $600\text{nm}$ are placed a distance $1.0\times {10}^{-2}\text{cm}$ apart. A detector can be moved on the line $S_{1}P$, which is perpendicular to $S_1{S}_2$. The maximum path difference at the detector as it is moved along the line $S_{1}P$ is

1. $1.0\times {10}^{-2}\text{cm}$
2. $2.0\times {10}^{-2}\text{cm}$
3. $3.0\times {10}^{-2}\text{cm}$
4. $4.0\times {10}^{-2}\text{cm}$

Q. Young's double slit experiment apparatus shown in figure , $D>>d$ and $d=6\lambda$. Find total number of maxima on the screen.

1. $11$
2. $10$
3. $5$
4. $6$

Q.

A thread carrying a uniform charge $\lambda$ per unit length has the configurations shown in Fig. $a$ and $b$. Assuming a curvature radius $R$ to be considerably less than the length of the thread, find the magnitude of the electric field strength at the point $O$.

Q. Two sources $S_1$ and $S_2$, emitting light of wavelength $600\text{nm}$, are placed a distance $1.0\times {10}^{-2}\text{cm}$ apart. A detector can be moved on the line $S_{1}P$, which is perpendicular to $S_1{S}_2$. What would be the minimum path difference (Approximately) at the detector, as it moves along the line $S_{1}P$?

1. $\text{zero}$
2. $d$
3. $d/2$
4. $\text{infinity}$

Q. In Young's double slit experiment distance, between two sources is $0.1mm$. The distance of the screen from the source is $20cm$. Wavelength of light used is $5460\stackrel{0}{A}$. Then, angular position of the first dark fringe is:

1. ${0.31}^{\circ }$
2. ${0.08}^{\circ }$
3. ${0.20}^{\circ }$
4. ${0.16}^{\circ }$

Q. In double slit experiment fringes are obtained using light of wavelength $4800$ A${}^{\circ }$. One slit is covered with a thin glass film of refractive index $1.4$ and another slit is covered by a film of same thickness but refractive index $1.7$. By doing so the central fringe is shifted to fifth bright fringe in the original pattern. The thickness of glass film is :

1. $2\times {10}^{-3}$ mm
2. $4\times {10}^{-3}$ mm
3. $6\times {10}^{-3}$ mm
4. $8\times {10}^{-3}$ mm

Q. In Fresnel's biprism expt., a mica sheet of refractive index 1.5 and thickness 6 $\times$ 10${}^{-6}$m is placed in the path of one of interfering beams as a result of which the central fringe gets shifted through 5 fringe widths. The wavelength of light used is

1. 8000 $\stackrel{o}{A}$
2. 4000 $\stackrel{o}{A}$
3. 6000 $\stackrel{o}{A}$
4. 2000 $\stackrel{o}{A}$

Q. A beam of light of $\lambda =600nm$ from a distant source falls on a single slit 1 mm wide and the resulting diffraction pattern is observed on a screen 2m away. The distance between first dark fringes on either side of the central bright fringe is

1. 1.2 cm
2. 1.2 mm
3. 2.4 mm
4. 2.4 cm

Q. Interference fringes are produced by a double-slit experiment and a piece of plane parallel glass refractive index $1.5$ is interposed in one of the interfering beams. If the fringes are displaced through $30$ fringe widths for light of wavelength $6\times {10}^{-5}cm$, if the thickness of the plate is $3.6\times {10}^{-X}cm$. Find X?

Q. Light of wavelength $6328\stackrel{o}{A}$ is incident normally on a slit having a width of $0.2mm$. The angular width of the central maximum measured from minimum to minimum of diffraction pattern on a screen $9.0$ meters away will be about

1. $0.36degree$
2. $0.18degree$
3. $0.72degree$
4. $0.09degree$

Q. The wavelength of X-rays is of the order of

1. $1cm$
2. ${10}^{-4}cm$
3. ${10}^{2}cm$
4. ${10}^{-8}cm$

Q. Two sources $S_{1}and{S}_2$ emitting light of wavelength 600 nm are placed a distance $1.0\times {10}^{-2}$ cm apart. A detector can be moved on the line $S_{1}P$ which is perpendicular to $S_1{S}_2.$ Locate the position of the farthest minimum detected.

1. $S_{1}P$=0 m
2. $S_{1}P$=Infinite
3. $S_{1}P$= 6 m
4. $S_{1}P$= 1.7 m

Q. The central fringe of interference pattern produced by light of wavelength $6000\mathring{A}$ is found to shift to the position of $4^{th}$ bright fringe, after a glass plate of $\mu =1.5$ is introduced. The thickness of the glass plate is :

1. $4.8\mu m$
2. $8.23\mu m$
3. $14.98\mu m$
4. $3.78\mu m$

Q. A beam of light propagating at an angle ${\alpha }_1$ from a medium $1$ through to another medium $2$ at an angle ${\alpha }_2$. If the wavelength of light in medium $1$ is ${\lambda }_1$, the wavelength of light in medium $2$, (${\lambda }_2$) is

1. $\frac{\sin {\alpha }_1}{\sin {\alpha }_2}{\lambda }_1$
2. $\frac{\sin {\alpha }_2}{\sin {\alpha }_1}{\lambda }_1$
3. $\left(\frac{{\alpha }_1}{{\alpha }_2}\right){\lambda }_1$
4. ${\lambda }_1$

Q. In double-slit experiment using light of wavelength 600 nm, the angular width of a fringe formed on a distant screen is ${0.1}^{\circ }$. What is the spacing between the two slits?

Q. Monochromatic green light of wavelength $5\times {10}^{-7}$ $m$ illuminates a pair of slits $1$ $mm$ apart. The separation of bright lines on the interference pattern formed on a screen $2$ $m$ away is

1. $0.25$ $mm$
2. $0.1$ $mm$
3. $1.0$ $mm$
4. $0.01$ $mm$

Q. Two wavelengths of sodium light 590 nm and 596 nm are used, in turn, to study the diffraction taking place at a single slit of aperture $2\times {10}^{-4}$ m. The distance between the slit and the screen is 1.5 m. Calculate the separation between the positions of the first maxima of the diffraction pattern obtained in the two cases.

Q. The wavelength of X-rays is

1. $2000A^o$
2. $2A^o$
3. $1mm$
4. $1cm$

Q. One of the following wavelengths is absent and the rest are present in the X-rays coming from a Coolidge tube. Which one is the absent wavelength?

1. 25 pm
2. 75 pm
3. 50 pm
4. 100 pm.

Q. In YDSE experiment if slit separation is 0.4 mm and wavelength of light used is 400 nm, then number of maxima observed [for $\theta ={37}^{\circ }$] between C and P are

1. 598
2. 749
3. 224
4. 500