# JNTUH R13 1st year Physics Important Questions

13 Apr 2015 03:06 pm

**ENGINEERING PHYSICS IMPOTRANT QUESTIONS **

**UNIT-I **

- Explain bonding in solids and explain the types of bonding in solid?
- Define cohesive energy. Derive an equation for cohesive energy for a diatomic molecule?
- Define the following a) Unit cell b) Space lattice c) Lattice parameter d) Atomic radius e) Co-ordinate number f) Packing factor g) Define and explain bravias lattices with crystal systems.
- Explain the following structure a) Simple cubic b) Body centered cubic c) Face centered cubic d) Diamond e) Nacl
- a) Explain the crystal planes and directions with miller indices? b) Derive an equation for interplanar spacing or orthogonal crystal system?
- Derive Bragg’s law. Explain lave method and powder method?
- Explain the defects in crystals. Explain Berger vector?

**UNIT -2 **

- Explain dual nature ,deg-broglie hypothesis &matter waves
- Explain construction of davission's and germer experiment. Explain Heisenberg Uncertainty principle
- Derive the expressions for the following a)Schrodinger wave independent equation b)Physical significance of '?' c)Particle in 1-D BOx d)Density of energy states
- Define the following: a)Phase space b)Ensembles
- Distuingish between 3 Distribution functions
- Derive the eq'ns for the following a)Fermi energy level at different temp's b)Bloch theorem c)Kronig penny model d)Effective mass of electron with E (v/s) K Diagrams
- Classification of materials into 3 types &explian with BRILLIAN ZONES.

**UNIT-III **

- Define the following a) Electric dipole b) Dipole movement c) Dielectric constant d) Polarisability e) Susceptibility f) Displacement vector
- Derive the following equations a) Internal fields in solids (or) Lorentz method (or) Local fields in solids (or) clasius-mosotti equation. b) Expression for four polarization process.
- Explain the following a) Permeability b) Field intensity c) Magnetic induction (B) d) Magnetization e) Susceptibility
- Explain piezo and Ferro electricity?
- Explain origin of magnetic movement with Bohr magneton?
- Explain the classification of Dia, para, Ferro, Ferri, antiferro on the basis of magnetic movement?
- Explain the following a) Domain of ferro magnetism b) Hysterisis curve c) Hard and soft materials d) Superconductivity e) Meissner effect f) Type-I and Type-II superconductors g) Applications of superconductors.

**UNIT-4**

- Derive the following: (a) Interference in thin films. (b) Newton's rings experiment.
- Give an expression for Fraunhoffer Diffraction due to single slit and 'n' slits.
- Diffraction grating experiment.
- Explain the construction and working of Nicol's prism.
- Explain the following: (a) characteristics of LASERS. (b) Distinguish b/w Spontaneous and stimulated emission. (c) Population Inversion. (d) Lasing action. (e) Applications of LASERS.
- Give an expression for Einstein coefficients and their relations.
- Explain the construction and working of the following: (a) Ruby LASER. (b) He-Ne LASER. (c) Hetero and Homo semiconductor LASERS.
- What is FIBRE? Explain principle in optical fibre and their applications.
- Explain construction of a fibre. Give an expression for Acceptance angle, cone and Numerical aperture.
- Explain the types of fibres and optical fibres in Communication systems.

**UNIT-5**

- Distinguish between intrinsic and extrinsic semiconductors.
- Derive an expression for the density of holes in the valence band of an intrinsic Semiconductor
- Derive an expression for density of electrons in intrinsic semiconductors.
- Derive an expression for carrier concentration of p-type semiconductors.
- Explain Hall effect and its importance
- Explain the variation of Fermi level with temperature in the case of p-type semiconductors.
- Explain the variation of Fermi level with i. Donor concentration ii. Acceptor concentration, in the case of extrinsic semiconductors.
- What is Hall effect? Derive an expression for Hall coefficient for p-type semi-conductor.
- Derive an expression for density of holes in intrinsic semiconductors
- What is Hall effect? Derive an expression for Hall coefficient for n-type semiconductor.
- Derive an expression for carrier concentration of n-type semiconductors.
- Explain the variation of Fermi level with temperature in the case of n-type semiconductors.
- Derive an expression for density of electrons in intrinsic semiconductors.
- Explain the variation of Fermi level with temperature in the case of p-type semiconductors
- Derive an expression for carrier concentration of n-type semiconductors. Explain Hall effect and its importance. Derive an expression for density of holes in intrinsic semiconductors[7+8]

**Note : JNTUFORUM **Is Not Any Responsible If The Questions In the Exam Are Out Of These Important Questions.