A quartz crystal of thickness 1.5 mm vibrating with resonance. Calculate it’s fundamental frequency if the Young’s modulus of quartz crystal is 7.9×10^{10}N/m^{2} and density is 2650 kg/m^{3} .

Concept: Study of characteristics of unit cell of Diamond, ZnS, NaCl and HCP;

Explain with example how to determine crystal structure by Bragg’s X-ray spectrometer.

Concept: Bragg’S Law

Calculate the frequency and wavelength of photon whose energy is 75eV.

Concept: De Broglie Wavelength

Obtain one dimensional time dependent time independent Schrodinger equation.

Concept: Schrodinger’S Time Dependent Wave Equation

What is the significance of wave function ? derive the expression for energy eigen values for the free particle in one dimensional potential well.

Concept: Wave Function

Draw the energy band diagram of p-n junction diode in forward and reverse bias condition .

Concept: Fermi Level Diagram for P-N Junction

Mobility of electron and hole in a sample of Ge at room temperature are 0.36 m^{2 }/V-sec and 0.17m^{2 }/V-sec respectively. If electron and holes densities are equal and it is 2.5 ×10^{13 }/cm^{3 }, calculate its conductivity.

Concept: Conductivity, mobility, current density (drift & diffusion) in semiconductors(n type and p type)

State the Hall effect. Derive the expression for Hall voltage and Hall coefficient with neat diagram.

Concept: Hall Effect

What is photovoltaic effect? Explain the principle and working of solar cell.

Concept: Applications of semiconductors : Rectifier diode, LED, Zener diode, Photo diode, Photovoltaic cell, BJT, FET, SCR., MOSFET

“Superconductor is a perfect diamagnetic”, Explain.

Concept: Meissner Effect

What is reverberation time? How it is important ? write the factors affecting reverberation time.

Concept: Reflection of Sound(Reverberation and Echo)

A hall of dimension 25×18×12m^{3 }has an average absorption coefficient 0.2. find the reverberation time. If a curtain cloth of area 150m^{2 }is suspended at the centre of Hall with coefficient of absorption 0.75, What will be the reverberation

time?

Concept: Reflection of Sound(Reverberation and Echo)

State the piezoelectric effect. With neat circuit diagram explain the principle and working of piezoelectric oscillator .

Concept: Piezoelectric Oscillator

What are crystal imperfections Mention any two significance of it .

Concept: Introduction to Crystallography

Draw and explain the unit cell of sodium chloride (NaCl) crystal determine effective number of NaCl molecule per unit cell and co-ordination number.

Concept: Study of characteristics of unit cell of Diamond, ZnS, NaCl and HCP;

Explain analysis of crystal structure using Bragg’s X ray spectrometer

Concept: X-ray Diffraction

Calculate the critical radius ratio of an ionic crystal in ligancy-6 . what is the maximum size of cation in ligancy 6 configuration when size of anion is 2.02A°?

Concept: Study of characteristics of unit cell of Diamond, ZnS, NaCl and HCP;

Draw the unit cell of HCP structure and work out the no. of atoms per unit cell.

Concept: Study of characteristics of unit cell of Diamond, ZnS, NaCl and HCP;

What is the principle of solar cell? Write its advantages and disadvantages

Concept: Study of characteristics of unit cell of Diamond, ZnS, NaCl and HCP;

Draw the following : (1,-1,3) ,(2,0,0) , [0,0,-1]

An electron is accelerated through 1200 volts and is reflected from a crystal. The second order reflection occurs when glancing angle is 60°. Calculate the inter planar spacing of the crystal.

Concept: Introduction to Crystallography