BE Mechanical Engineering सत्र १ (इंजीनियरिंग) - University of Mumbai Important Questions for Applied Physics 1

Find the following parameter for DC(Diamond Cubic) structure:- 
⦁ No. of atoms per unit cell.
⦁ Co-ordination number.
⦁ Nearest atomic distance.
⦁ Atomic radius.
⦁ APF.

Why X-rays are used to study the crystal structure?

With neat diagram of unit cell, explain the structure of NaCl crystal and calculate the no .of ions per unit cell, co ordination no. and lattice constant. Calculate the packing factor of NaCl crystal assuming the radius of _Na+is 0.98 A° and radius of Cl is 1.81 A°. 

Define ligancy and critical radius ratio. Calculate critical radius ratio for ligancy 8. 

‘Crystal acts as three dimensional grating for X-rays’, explain.

 With neat diagram of unit cell , explain the structure of HCP crystal and calculate the no. of ions per unit cell, co ordination no., lattice constant and packing factor of the structure.

Define ligancy and critical radius ratio. Calculate critical radius radio for ligancy 6.

Draw (123)

Draw(321)

Draw (102)

Explain with Diagram Hcp Unit Cell Based on Lattice Parameters.

Derive Bragg's condition for X-ray diffraction. Monochromatic X rays are
incident on a crystal. If the first order rejection is observed at an angle of 3.4•, at
what angle would second order reflection expected.

A quartz crystal of thickness 1 mm is vibrating at resonance. Calculate its fundamental frequency. (Assume that for quartz, Y= 7.9x 1010 N/m2 and p = 2.650 gm/cc.

Define Ligancy. Find the value of critical radius ratio for Ligancy 3.

Explain Point defects in crystals.

Write schrodinger’s time dependentand time independent wave equations of matter waves in one dimensional and state physical significance of these Equations. 

Describe with the necessary theory the davisson and german establishing wave nature of electrons. Calculate the de-broglie wavelength of an alpha particle accelerating through a potential difference of 200 volts given :- mass of alpha
particle = 6.68×10^-27kg. 

What do you mean by group and phase velocity? Show that the de-Broglie group velocity associated with the wave packet is equal to the velocity of the particle.

An electron is confined in a box of dimension 1A°. calculate minimum uncertainty in its velocity.

Derive Schrodinger time dependent wave equation for matter waves.