Determination of Planck S Constant Using LED S of Different Wavelengths
(An Autonomous Institution, Affiliated to V.T.U, Balagavi)
Mysuru Road, Bengaluru - 560059
DEPARTMENT OF PHYSICS
Semester: I/II
ENGINEERING PHYSICS( Theory and practice)
Course Code: / 16PH12/16PH22 / CIE Marks:100+50=150
Hrs/Week: L:T:P:S / 4:0:2:0 / SEE Marks:100+50=150
Credits: / 05 / SEE ( Theory)Duration : 3 Hrs
SEE (Practice)Duration : 3 Hrs
UNIT-I
Dielectrics and Thermal conductivity
Dielectrics: Electric dipole, Dipole moment, Field due to electric dipole at a point in a plane. Polarization of dielectric materials: Types of polarizations, frequency dependence of polarization mechanisms, dielectric loss. Internal field in solids: for one dimensional infinite array of dipoles (Lorentz field), Clausius - Mossotti equation.
Thermal conductivity: conduction of heat in solids, steady state, coefficient of thermal conductivity, thermal conductivity of a good conductor by Searle’s method and thermal conductivity of a poor conductor by Lee’s and Charlton’s method. / 09h
UNIT-II
Quantum Mechanics
Black body radiation spectrum, Laws of black body radiation spectrum, Plank’s quantum theory, Review of Photoelectric effect and Compton effect. Wave –particle duality, de-Broglie hypothesis. Matter waves: properties of matter waves, wave packet, group velocity, phase velocity and their relations. Application of matter waves: Scanning Electron Microscope (SEM) – construction and working. Uncertainty principle: illustrations-Non-confinement of electron inside the nucleus and broadening of spectral lines. Setting up of one dimensional time independent Schrodinger’s wave equation-wave function, physical significance of wave function, Eigen function, Eigen values. Application of Schrodinger’s wave equation: Free particle, Particle in a one dimensional potential well of infinite depth. Problems / 11h
UNIT-III
Electrical conductivity in metals and semiconductors
Review of Classical free electron theory, Quantum free electron theory. Fermi energy and Fermi factor in metals, variation of Fermi factor with temperature. Density of states and carrier concentration in metals. Hall effect-Determination of number and sign of charge carriers. Band theory of solids, (qualitative approach).
Intrinsic semiconductors: carrier concentration, concept of effective mass (qualitative), derivation of electron and hole concentration, intrinsic carrier concentration, Fermi level in intrinsic semiconductors, Expression for the energy gap of intrinsic semiconductors.
Extrinsic semiconductors: Types of extrinsic semiconductors, doping methods (qualitative). Variation of carrier concentration in extrinsic semiconductors with temperature, variation of Fermi level in extrinsic semiconductors with temperature and impurity concentration. Hall effect in semiconductors. / 10h
UNIT-IV
Oscillations and Waves
Simple Harmonic Motion, Characteristics of Simple harmonic motion. Un damped / Free vibrations, differential equations of un damped / free vibrations and solutions. Examples of Simple harmonic oscillators a) Spring and Mass system, b) Torsional Pendulum. Damped vibrations: Differential equations of damped vibrations and solutions. Forced vibrations: Differential equations of forced vibrations and solutions, Resonance. Examples of forced vibrations- LCR circuits. Problems. / 09h
UNIT-V
Lasers and Optical Fibers
Basic principles of Laser: Absorption and emissions, Einstein’s coefficients. Energy density in terms of Einstein coefficients, conditions and requisites of laser. Types of lasers: Helium -Neon Laser, Semiconductor diode Laser. Characteristics of laser beam. Industrial applications of lasers: laser cutting, welding and drilling, measurements of pollutants in atmosphere.
Principle of Optical fibers: propagation mechanism, condition for propagation, acceptance angle and numerical aperture. Modes of propagation, types of optical fibers. Attenuation: Absorption, scattering and radiation loss, attenuation coefficient. Application of optical fiber in point to point communication, advantages of optical fiber communication over electrical mode of communication. / 08 h
Course Outcomes: After completing the course, the students will be able to
CO1 / Understand the fundamental concepts of Optical Physics, Quantum mechanics, wave theory and conductivities
CO2 / Apply the concepts of Optical Physics, Quantum mechanics, wave theory and conductivities in Engineering domain.
CO3 / Analyze the theoretical concepts and investigate in the laboratory.
CO4 / Demonstrate team work and effective reporting
LAB EXPERIMENTS
- Verification of Stefan’s law
- Determination of Planck’s constant using LED’s of different wavelengths
- Analysis of the frequency response of Series LCR circuits and determination of inductance of the given inductor.
- Using four probe to determine the resistivity of given semi conductors.
- Determination of moment of inertia of an irregular body by Torsional oscillations.
- Determination of energy gap of given thermally sensitive resistors.
- Determination of Fermi energy of conductors
- Identification of the nature of the given semiconductors and determination of their Hall coefficient and carrier concentration of given materials.
- Determination of Dielectric constant by charging and discharging of a capacitor.
- Using Searle’s method to find the thermal conductivity of good conductors
- Thermal conductivity of a poor conductor by Lee’s and Charlton’s method
- Determination of divergence angle of a laser beam
- Determination of numerical aperture of an optical fiber
10 Experiments are GUIDED experiments
03 Experiments involving experiential learning.
Text Books
1 / A Text book of Engineering Physics
Dr. M N Avadhanulu, Dr. P. G. Kshirsagar, S. Chand & Company Private limited. Revised edition 2015.
2 / Engineering Physics
R K Gaur and S L Gupta, Dhanpat Rai Publications, Revised edition 2011.
Reference Books
3 / Fundamentals of Physics
Haliday & Resnic & Walker, John Wiley & Sons 2010, ISBN: 9971-51-330-7.
4 / Engineering Physics
Hitendra K Malik and A K Singh, Tata McGraw Hill Education Private Limited, 2009, ISBN: 978-0-07-067153-9.
CO-PO Mapping
CO/PO / PO1 / PO2 / PO3 / PO4 / PO5 / PO6 / PO7 / PO8 / PO9 / PO10 / PO11 / PO12
CO1 / 2 / 3 / 2 / 1 / - / - / - / - / - / - / - / 2
CO2 / 1 / 3 / 3 / 1 / - / - / - / - / - / - / - / 2
CO3 / 1 / 3 / 3 / 3 / - / - / - / - / - / - / - / 2
CO4 / 1 / 3 / 2 / 1 / - / 2 / - / - / 2 / 2 / - / 2
High-3 : Medium-2 : Low-1