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INSTRUCTIONS
(1) Assume appropriate data and state your reasons
(2) Marks are given to the right of every question
(3) Draw neat diagrams wherever necessary

Choose correct answers for the following;
1(a)(i) With increase in temp of black body radiation maximum intensity position shifts towards.
A) Shorter wavelength
B) Larger wave length
C) No change
D) None of these
1 M
1(a)(ii) Green light incident on a surface releases photoelectrons from the surface. If the blue light is incident on a surface the velocityof electrons.
A) Increases
B) Decreases
C) Remains same
D) Becomes zero
1 M
1(a)(iii) The group velocity of the practicle is 3×106 m/s, whose phase velocity is
A) 6.06×106m/s
B) 3×1010m/s
C) 3×106m/s
D) 1.5×1010m/s
1 M
1(a)(iv) Electron behaves as wave, beacuse they can be
A) Deflected Electric field
B) Deflected by magnetic field
C) Diffracted by crystals
D) Ionize a gas
1 M
1(b) Describe Davison and Germer's experiment for the justification of de -- Broglie wave length.
6 M
1(c) Derive an expression for de -- Broglie wavelength using the concept of group velocity.
6 M
1(d) A particle of mass 0.5mev/C2 has kinetic energy. 100EV, Find its de-Broglie wavelength where 'C' is the velocity of light.
4 M

Choose correct answers for the following;
2(a)(i) The uncertainty inthe determination of position of an electron is$\left ( \frac{h}{3\pi } \right )$, then the\begin{align*} A) \dfrac{1}{4}\\ B)\dfrac{4}{3} \\ C)\dfrac{3}{4}\\ D)3 \end{align*}
1 M
2(a)(ii) If the electron exists in a nuclear, its energy must have a minimum energy of about
A) 4 Mev
B) 10 Kev
C) 20 Kev
D) 20 Mev
1 M
2(a)(iii) Wave function is an acceptable wave function, if it is
A) Finite every where
B) Continous every where
C) Single valued everywhere
D) Having all these properties
1 M
2(a)(iv) The nomalization of wave function is always possible if \begin{align*} A)\int ^{\infty}_{-\infty}\Psi ^*dx= infinite\\ B) \int_{ -\infty }^{\infty}\Psi ^*dx=finite\\ C)\int_{-\infty}^{-\infty}\Psi^*dx=0\\ D)\text{All of these}\end{align*}
1 M
2(b) State and explain Heisenberg's uncertainty principle.
4 M
2(c) Solve the Schrodinger wave equations for allowed energy values in case of particle in potential box of infinite height.
8 M
2(d) Estimate the time spent by an atom in the excited state during the excitation and deexcitation processes, when a special line o wavelength 546nm and width 10-5nm is emitted.
4 M

Choose correct answers for the following;
3(a)(i) For ordinary metals the resistivity versus tempreature curve at OK
A) has a positive intercept
B) has a negative intercept
C) goes through the origin
D) None of these
1 M
3(a)(ii) Mobility of electron is
A) Reciprocal
B) Flow of electrons per unit tie
C) Reciprocal of resistivity
D) Average electron drift velocity / unit electric field.
1 M
3(a)(iii) Average drift velocity Vd of electrons in a metal is related to the electric field and coilision timeτ\begin{align*}A)\sqrt{\frac{m}{eE}_{\tau}} \\ B)\frac{eE\tau }{m} \\ C)\sqrt{\frac{eE\tau}{m}} \\ D) \frac{m}{eE\tau}\end{align*}
1 M
3(a)(iv) The Fermi energy theory of metal at absolute zero temprature is proportional to
A)n1/3
B) n3/2 C) n2/3 D) n2
1 M
3(b) Using free electrons theory derive an expression for elecctrical conductivity in metals.
6 M
3(c) Explain how quantum free electron theory succeeds on overcoming the drawback of classical free electron theory.
6 M
3(d) Calculate the probability of an electron occupying an energy level 0.02ev above the fenal level at 200K and 400K in a material.
4 M

Choose correct answers for the following;
4(a)(i) When a dielectric material is subjected to an external electric field, the internal field will be
A) lesser than the applied field
B) greater than the applied field
C) same as the applied field
D) Zero
1 M
4(a)(ii) The energy due to dielectric loss appears as
A) light energy
B) heat energy
C) sound energy
D) electromagnetic energy
1 M
4(a)(iii) Piezoelectric effect is the production of energy by
A) chemical effect
B) varying field
C) tempreature
D) pressure
1 M
4(a)(iv) For Ferro magnetic substance, the Curie - Weirs law is given by \begin{align*}A)\Psi =\frac{C}{T} \\ B)\Psi =\frac{T-\Theta }{C} \\ C)\Psi =\frac{C}{T-\Theta } \\D)\frac{C}{T+\Theta }\end{align*}
1 M
4(b) Define Dielectric Polarications. Discuss any three types of polarization mechanism dielectrics.
7 M
4(c) Distinguish between Hard & soft magnetic materials.
5 M
4(d) A solid dielectric material has electronic polarizability 7×ao-40 F m2. If it is an cubic structure,calculate the realative permittivity of the materials. It has3×1028 atoms/m3
4 M

Choose correct answers for the following;
5(a)(i) The relation between Einstein's coefficient A and B is\begin{align*}A)\frac{8\Pi h{\lambda^3}}{C^3} \\ B)\frac{8\Pi {h^2\lambda ^3}}{C^3} \\ C)\dfrac{8\Pi h{y^3}}{C^3} \\ D)\dfrac{8\Pi h{y^3}}{C^2}\end{align*}
1 M
5(a)(ii) Condition for lasing action is
A) Excitations
B) Absorption
C) Emission
D) Population inversion
1 M
5(a)(iii) Pumping process in Ga As laser is by
A) Optical pumping
B) Forward bias
C) Electric discharge
D) None of these
1 M
5(a)(iv) In recording the image on the photographic plate, the reference beam and the object beam undergo ______at the photographic plate
1 M
5(b) Discuss posssible ways through which radiation and matter interaction takes place.
6 M
5(c) Describe the construction and working of He-Ne laser with the help of energy level diagram.
6 M
5(d) A medium in thermal equilibrium at tempreature 300K has two energy levels with a wavelength sepration 1μm. Find the ratio of densities of the upper and lower levels.
4 M

Choose correct answers for the following;
6(a)(i) Fractional index change for on optical fiber with core and cladding refractive indices1.563 and 1.498 respectively,
A)0.00415
B) 0.04150
C) 0.04300
D)0.00400
1 M
6(a)(ii) In grated index fiber the refractive index of the core varies
A) Linerarly
B) Parabolin manner
C) exponential manner
D) None of these
1 M
6(a)(iii) The critical field strength of a superconductor
A) is inversely proportional to temperature
B) is proportional to tempreature
C) varies with tempreature
D) is independent of tempreature
1 M
6(a)(iv) The phase transition from superconducting to normal state can be effected bymeans of Meissner effect. This peinciple can be used in
A) switching devices
B) measuring technology
C) NMR tomography
D) Bubble chambers
1 M
6(b) Describe Type-I and Type-II super conductors.
5 M
6(c) What is numerical aperture?Obtain an expression for numerical aperture and obtain the condition for propagation in optical fiber.
7 M
6(d) The attenuation of light in an optical fiber is 3.6 dB/km. What fractional intensity remains after 1 km and 2 km?
4 M

Choose correct answers for the following;
7(a)(i) The coordination number incase of FCC is
A) 6
B) 8
C) 12
D) 16
1 M
7(a)(ii) The relation between lattice constant 'a' and atomic radius 'r' in case of BCC structure is \begin{align*}A) a=\sqrt{2r} \\ B) a=\frac{4}{\sqrt{3}} r \\ C) a=\sqrt{2r} \\ D) a=2r \end{align*}
1 M
7(a)(iii) In a cubic crystal a plane make interrupts 1, -3, 1 on the X, Y and Z axes respectively. The miller indices of the plane are \begin{align*} A) \left ( \bar{3} \ 1\ \bar{3}\right ) \\ B)\left ( 3 \ \bar{1}\ 3 \right ) \\ C)\left ( 1 \ \bar{3} \ 1 \right ) \\ D)\left ( \bar{1}\ 3\ \bar{1}\right ) \end{align*}
1 M
7(a)(iv) The packing fraction of diamond crystal structure is
A) 34 percentage
B) 52 percentage
C) 68 percentage
D) 74 percentage
1 M
7(b) Derive an expression for interplanar spacing interm of miller indices.
5 M
7(c) Explain in brief the seven crystal system with neat diagram.
7 M
7(d) A beam of X-rays of wavelength 0.071nm is diffracted by (110) plane of rock salt with lattice constant of 0.28nm. Find the glancing angle for the second order fraction.
4 M

Choose correct answers for the following;
8(a)(i) Bulk material reduced in two direction is known as
A) quantum dot
B) quantum particle
C) film
D) quantum wire
1 M
8(a)(ii) Fullerene is
A) A sheet of carbon atoms rolled up into long tube
B) Sixty carbn atoms arranged in the shape of a foot ball
C) One dimensional array of atoms
D) Three dimensional array of atoms.
1 M
8(a)(iii) The elastic behaviour of a liquid is characterized by its
A) Young's modulus
B) Modulus of rigidity
C) Bulk modulus
D) Poisson's ratio
1 M
8(b) What are Nanomaterials? Explain carbon nanotunes and their applications by giving their physical properties.
8 M
8(c) Explain in the principle and method of non desturctive method of testing of materials using ultrasonic's.
8 M
8(iv) A constant testing of product with out carrying any damage is called
A) Mines testing
B) Destructive testing
C) Non destructive testing
D) Random testing.
1 M

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