CS MAINS PHYSICS Paper-II
IC-DRN-N-RIZB I
Maximum Marks 250

SECTION-A
Q. Find the deBroglie wave length of a neutron and an electron moving with a kinetic energy of SOO eV. eV 1.602 x 10-19 10
Q. 1(b)The mean life time of Lambda particle is 2.6 x 10-10 s. What will be the uncertainty in the determination of its mass in eV 10
Q. If x and are the position and momentum operators, prove the commutation relation -2ilip. 10
Q. Given that the spacing between vibrational levels of CO molecules is 8.45 x 10-2 eV of energy. Find the force constant of the molecule. 10
Q.1(e) Write down Pauli spin matrices. Express Jx, Jy and Jz in terms of Pauli spin matrices. 10
Q. Using the commutation relations px pz]=1h deduce the cOnlmutation relation between the components of angular momentum operator L. Lyl =ih Lz Lz] =ih Lx and [Lz,Lxl =ih Ly . 20
Q. Obtain the time-dependent Schrodinger equation for a particle. Hence deduce the timeindependent Schrodinger equation. 20
Q. A sample of a certain element is placed in a magnetic field of flux density 0.3 tesla. How far apart is the Zeeman component of a spectral of wavelength 4500 A Given: 1.76 x 1011 clkg, c 3.0 x 108 ms-I . 10
Q. Solve the Schrodinger equation for a particle of mass m confined in a one-dimensional potential well of the form V when 0 x L 00, when x x L Obtain 'the discrete energy values and the normalized eigen functions.
Q. 3(b)Discuss the vibrational spectra of a diatomic molecule treating it as an anharmonic oscillator. 20
Q. An electron is moving in a one dimensional box of infinite height and width 1 A. Find
the minimum energy of electron. 10
Q. Obtain an expression ror the normal Zeeman shift. Illustrate the Zeeman splitting of spectral lines of H atom and the allowed transitions for the 1 and I 2 states. 20
Q. Explain how the nuclear spin I depends on the mass number A and atomic number Z of atoms. 10
Q.
Obtain an expression for the resonance condition in NMR. 10
Explain the relaxation processes in NMR spectroscopy. 10
SECTION-B

Q.5(a) Explain why stable light nuclei have equal number of protons and neutrons whereas heavy nuclei have excess of neutron. 10
Q. 5(b)It is possible to estimate the nuclear radius from the study of alpha decay Explain
how. 10
Q. 5(C)The velocity of sound in f.c.c. gold and f.c.c. copper is 2100 m/s and 3800 m/s respectively. If the Debye temperature of copper is 348 then determine the Debye temperature of gold. Take the densities of gold and copper as 1.93 x 104 kg/m3 and 0.89 x 104 kg/m3 respectively. 10
Q.5(D) How does the energy gap in superconductors differ from the energy gap in insulator How does it vary with temperature for superconductors 10
Q. In a cubic unit cell, find the angle between normals to the plane and (121). 10
Q. Explain the working of SEM and TEM and highlight the major differences in principles. . Draw neat schematic diagrams. 20
Q. Give the basic structure of n-channel depletion type MOSFET. Draw the drain currentdrain voltage characteristics both in depletion as well as enhancement modes. 20
Q. How are elementary particles classified on the basis of their participation in fundamental interaction 10
Q.
What are salient features of nuclear forces 10
Discuss Yukawa's theory of nuclear forces. 10
Q.
How does liquid drop model explain fission 10
What are the limitations of shell model 10
Q. Lead in the superconducting state has critical temperature of 6.2 K at zero magnetic field and a critical field of 0.064 MAm-1 at 0 K. Determine the critical field at 4 K. 10
Q. What is reciprocal lattice and why is it named so Derive the relationships for the primitive translation vectors of the reciprocal lattice in terms of those of the direct lattice. 20

Q.8(b)hat are the magic numbers in nuclei List the experimental evidences indicating their existence. 20
Q. An electric field of 100 V1m is applied to a sample bf n-type semiconductor whose Hall coefficient is -0.0125" m3/coulomb. Determine the current density in the sample assuming Ilx 0.36 m2 v-Is-I. 10