www.alagappauniversity.ac.in MPhil Physics Model Question Paper Distance Education : Alagappa University

[hemalathaijt]

Document Described : Alagappa University
M.Phil. (Physics) (Non-Semester) DEGREE EXAMINATION, MAY 2011.
ADVANCED PHYSICS
(2006 Batch)
Time : Three hours Maximum : 100 marks

http://www.alagappauniversity.ac.in/...9&college_id=2
http://www.alagappauniversity.ac.in/files/question_paper/2-M.Phil%20(Physics).doc

Answer any FIVE questions.
All questions carry equal marks.
(5 ? 20 = 100)

1.(a)Solve the Klein – Gordon equation for a relativistic particle. What are the difficulties associated with this equation?
(b)What do you mean by spinor?

2.Explain the metal – ligand charge transformation based on the Huckel molecular orbital theory.

3.(a)Discuss, with necessary theory, the construction and working of a heterojunction semiconductor laser.
(b)Calculate the number of photons/s of a diode laser with a wavelength of 650 nm and 0.1 mW optic power.

4.(a)Define numerical aperture. Derive expressions for it and the angle of acceptance of fibre, in terms of the refractive index of the core and the cladding of the fibre.
(b)Calculate the numerical aperture and acceptance angle of a fibre with a core index 1.52 and a cladding index of 1.5.

5.(a)What are the different units of a fiber communication system? Explain their functions.
(b)If the intensity of a signal is divided in the ratio of 50 : 50, what will be the reduction in the intensity of the divided signal in dB?

6.How is the non-linear term in the Hamiltonian of a relativistic particle linearized? Explain the outcome of the result. How is the Hamiltonian modified in a non-central force?

7.What are Feynman diagrams? Discuss their applications.

8.Explain the concept of spectral hole burning. How is it effectively employed in spectroscopy?