Punjab Technical University 2011-2nd Sem B.Tech B Tech ester, , Physics , Reappear , - 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)Define remanence and coercivity.

b)Explain the term metastable state and its significance.

c)Explain the term normalized frequency.

d)Give examples of solenoidal and irrotational fields.

e)What is the r6st mass of photon.

f)Why we X - rays only for crystal structure determination?

g)How does the outcome of quantum mechanics differ from those of classical mechanics in harmonic oscillator.

h)What is the difference ranging from perfect diamagnet and superconductor?

i)What effect does the target metal have on the continuous x _ ray spectrum?

j)What is the de - broglie concept of matter waves?

part - B [8 Marks Each)

Q2)a)Using Gausss legal regulations of electrostatics, obtain the electric field due to a uniformly charged solid sphere at a point, which is lying outside the sphere.

b)In an electric field the electric potential is provided by U(x,y, z) = (4x2+ 3y2 + 6z2) . compute the electric field at point(1,1,1).

Q3) (a) Briefly define the phenomenon of magnetic hysteresis and why it occurs for ferromagnetic and ferrimagnetic materials.

(b) What is the difference ranging from soft and hard magnetic materials.

Q4) discuss the subsequent terms:
(i) Population inversion.
(ii) Semiconductor laser,
(iii) Holography.

(b) The light of wavelength 660 nm has a wave train of length is 32 x 10m. compute the coherent time?

Q5) (a) obtain the core radius necessary for single mode operation at 820 nm of a step index fibre with n1= l.480 and n2 = l.478.

(b) Differentiate ranging from material dispersion and pulse dispersion. Write down different kinds of losses in optical fibre.

part - C (8 marks each)

Q6) (a) An electron is moving with a speed of 0.9c. compute its total energy and obtain the ratio of Newtonian kinetic energy to the relativistic kinetic energy.

(b) define Michelson Morley experiment and show the negative outcomes found from this experiment were interpreted.

Q7) (a) compute the wavelength of X - rays produced when the potential difference is 12400 volts.

(b) Differentiate ranging from characteristic and continuous X - rays provide a few industrial and engineering applications of X – rays.

(c) What is Moseleys law? provide its applications.

Q8) (a) Derive an expression for the time independent Schrodinger wave formula.

(b) An electron.is bound by potential which closely approaches an infinite value formulate the least 3 permissible quantum energies the electron can have

Q9) (a) What do you understand by kind - I and kind - II superconductors? discuss with examples.

(b) elaborate London equations? obtain the expression for the penetration depth of a superconductor.

Earning:   Approval pending.