OCET MTech Nano Science and Nano Tech Model Question Paper Panjab University : www.exams.puchd.ac.in

[hemalathaijt]

Panjab University
OCET 2011
Subject : M. Tech. (Nano Science and Nano Tech.)
Time : 90 minutes Number of Questions : 75 Maximum Marks : 75

Model Question List : http://exams.puchd.ac.in/show-noticeboard.php?id=211
Model Question Paper : http://exams.puchd.ac.in/includes/no...928-07-MTN.pdf

1. In a metal at 0 K, the Fermi energy is :
(A) the highest energy of any electron (B) the lowest energy of any electron
(C) the mean thermal energy of the electrons (D) the energy of the top valence band

2. A hole refers to :
(A) A proton
(B) A positively charged electron
(C) An electron that has somehow lost its charge
(D) The absence of an electron in an otherwise filled band

3. In addition to the daughter nucleus and electron or positron, the products of a beta decay includes :
(A) A neutron (B) A neutrino
(C) A proton (D) An alpha particle

4. The energy gap (in eV) between the valency and conduction bands of an insulator is of the order :
(A) 0.001 (B) 0.1
(C) 10 (D) 100

5. The number of states in a shell with a principal quantum number n = 3 is :
(A) 3 (B) 9
(C) 15 (D) 18

6. To observe the Zeeman effect one uses :
(A) A strong uniform magnetic field
(B) A strong non-uniform magnetic field
(C) A strong uniform electric field
(D) Mutually perpendicular electric and magnetic fields

7. Characteristic K X-radiation of an element is caused by :
(A) Stoppage of electrons by the nucleus
(B) Ejection of an electron from an outer shell
(C) Transition of an electron to the innermost orbit
(D) Scattering of the incident radiation with a change of wavelength

8. The ground state energy of a hydrogen atom is ?13.6 eV. The minus sign indicates :
(A) The kinetic energy is negative
(B) The potential energy is positive
(C) The electron might escape from the atom
(D) The electron and proton are bound together

9. Which of the following crystal structures has closest packing of atoms ?
(A) Simple cubic structure
(B) Body centered cubic structure
(C) Face centered cubic structure
(D) Hexagonal close packed (hcp) structure

10. A real gas is changed slowly from the state I to state II, during this process no work is done on or by the gas, this process must be :
(A) isothermal (B) adiabatic
(C) isovolumic (D) isobaric

11. Pulling the plates of an isolated charged capacitor apart :
(A) Increases the capacitance
(B) Increases the potential difference
(C) Does not affect the potential difference
(D) Does not affect the capacitance

12. If an electron has zero orbital angular momentum, the magnitude of its dipole moment is equal to :
(A) Zero (B) Half the Bohr magneton
(C) A Bohr magneton (D) Twice a Bohr magneton

13. For an electromagnetic wave the direction of the vector B E r r × gives :
(A) The direction of the electric field
(B) The direction of the magnetic field
(C) The direction of the wave propagation
(D) The direction of the emf induced by the wave

14. Alternating voltage of frequency 50 Hz is used as the input of a full wave rectifier. Number of pulses of the rectified output obtained in one second will be :
(A) 25 (B) 50
(C) 100 (D) 200

15. The largest X-ray wavelength that could be diffracted by rock salts crystal planes with a separation of 0.282 nm is :
(A) 0.564 nm (B) 0.282 nm
(C) 0.0282 nm (D) 0.141 nm