B.E. I & II Sem (All Branches)

I & II SEMESTER

103/203. PHYSICS

Units & Contents of the Subject

I. Interference of Light

Preliminary:[ Interference as superposition of waves in space. Intensity variation. Bright and dark fringes.Fringe width. Conditions for observing interference of Light.]

  • Newton’s Rings: Theory and experiment for determining wavelength of light and refractive index of liquid

  • Michelson’s Interferometer: Production of circular & straight line fringes, Determination of wavelength of light, Determination of wavelength separation of two nearby wavelengths

  • Interference in Optical Technology: elementary idea of anti reflection coating and interference filters

Polarization of Light

  • Plane, circular and elliptically polarized light on the basis of electric (light) vector, Malus Law

  • Double Refraction: Qualitative description of refraction, Phase retardation plates, Quarter and half wave plates construction working and use of these in production and detection of circular and elliptically polarized light

  • Optical Activity: Optical activity and law of optical rotation, Specific rotation and its measurement using the half shade and Bi-quartz devices

II. Diffraction of Light and Holography:

Preliminary: [Diffraction as a consequence of limiting wavefront. Fresnel’s and Fraunhofer’s diffraction. Interference and Diffraction. Diffraction at single slit qualitative description.]

  • Single Slit Diffraction: Quantitative description of single slit, Positions of maxima / minima and width of central maximum, Intensity variation

  • Diffraction Grating: Construction and theory, Formation of spectrum by plane transmission grating, Missing and overlapping of spectra, Determination of wavelength of light using plane transmission grating

  • Resolving Power: Geometrical & Spectral, Reyleigh criterion, Resolving power of diffraction grating, Electron microscope and its resolving power

Holography

  • Holography versus photography, Basic theory of holography, Basic requirement of a holographic laboratory

  • Application of holography in microscopy and interferrometry

III. Coherence

  • Spatial and temporal coherence, Coherence length, Coherent time and ‘Q’ factor for light 

  • Visibility as a measure of coherence

  • Spatial coherence and size of the source

  • Temporal coherence and spectral purity

Lasers

  • Theory of Laser Action: Einstein’s coefficients components of a laser, Threshold condition for laser action

  • Theory, design and application of He-Ne and Semiconductor lasers

  • Elementary ideas of Q-switching and mode locking

Optical Fibers

  • Optical fiber as optical wave guide

  • Numerical aperture and maximum angle of acceptance

IV. Quantum Mechanics:

Preliminary: [Origin of quantum nature of light: Black body radiation and photoelectric effect. Unability of wave theory of light to explain photoelectric effect. Einstein Photoelectric Equation. De-Broglie Matter waves. Uncertainity principle]

  • Compton effect and quantum nature of light

  • Schrödinger’s Wave Equation: Time dependent and time independent cases

  • Physical interpretation of wave function and its properties, boundary conditions

Applications of Schrödinger’s Equation

  • Particle in one and three dimensional boxes

  • Degeneracy barrier penetration and tunnel effect

  • Tunneling probability, – decay

Sommerfield’s Free Electron Gas Model

  • Postulates, Density of energy status, Fermi energy level

V. Special Theory of Relativity and Nuclear Detectors

 Preliminary: [Classical theory of relativity and Galalian Transformations. Michelson Morley Experiment. Explanation of negative result.]

  • Postulates of special theory of relativity, Lorentz transformations relativity of length, mass and time

  • Relativistic velocity addition, Mass – Energy relation

  • Relativistic energy

  • Velocity of light in moving media, Sagnac’s formula and its application in optical gyroscopes

Nuclear Radiation Detectors

  • Characteristics of gas filled detectors: general considerations

  • Construction, working and properties of : Ionization chamber, Proportional Counter, G.M. Counter and Scintillation counter