Punjab Technical University 2009-1st Sem B.Tech B Tech ester, , Physics , Regular , - Question Paper

Time: three Hours
Maximum Marks: 60

Instruction to Candidates:
1) Section- A is Compulsory.
2) Attempt any 5 ques. from Section- B & C
3) choose at lowest 2 ques. from part - B & C

part – A [Marks 2*10=20]

Q1) a) discuss the term time dilatation?

b) What is the wavelength of He-Ne Laser, Semiconductor Laser?

c) discuss the term permittivity.

d) What is the significance of V-numbers in OFCs.

e) describe the importance of doping in semiconductors.

f) discuss the Isotopic effect in case of superconductors.

g) describe LASERS.

h) discuss the concept of ether.

i) Plot the graphs for soft and hard superconductors.

j) Differentiate ranging from group velocity and phase velocity.

part – B [Marks: eight Each]

Q2) (a) discuss the significance of Maxwells equations.

(b) discuss the term current density and compute the expression for it.

Q3) (a) Differentiate ranging from Step Index and Graded Index Fibers.

(b) compute the numerical aperture acceptance angle and the critical angle of a fiber having core
refractive index 1.5 and the cladding refractive index 1.45.

Q4) (a) discuss the working, construction and energy level diagram for Ruby laser.

(b) discuss the term spatial and temporal coherence.

Q5) (a) Differentiate ranging from hard and soft magnetic materials.

(b) Mention a few applications of Ferrite materials.

part – C [Marks: eight Each]

Q6) (a) discuss Michelson Morley experiment and explain its significance.

(b) discuss different postulates of Special theory of Relativity.

Q7) (a) Differentiate ranging from hard and soft X-Rays.

(b) describe Wave function and compute the expression for Time dependent Schrodinger Wave formula.

Q8) Differentiate ranging from photo electric effect and compton effect and compute the expression for Compton Shift.

Q9) (a) discuss BCS theory of superconductivity.

(b) compute the expression for penetration depth in superconductors.

Earning:   Approval pending.