GE: Waves and Optics (32225310)
Credit : 06 (Theory-04, Practical-02)
Theory : 60 Hours
Practical : 60 Hours
Course Objective
This course reviews the concepts of waves and optics learnt at school from a more advanced
perspective and goes on to build new concepts. It begins with explaining ideas of
superposition of harmonic oscillations leading to physics of travelling and standing waves.
The course also provides an in depth understanding of wave phenomena of light, namely,
interference and diffraction with emphasis on practical applications of the same.
Course Learning Outcomes
On successfully completing the requirements of this course, the students will have the skill
and knowledge to:
Understand Simple harmonic oscillation and superposition principle.
Understand different types of waves and their velocities: Plane, Spherical, Transverse,
Longitudinal.
Understand Concept of normal modes in transverse and longitudinal waves: their
frequencies and configurations.
Understand Interference as superposition of waves from coherent sources derived from
same parent source.
Demonstrate basic concepts of Diffraction: Superposition of wavelets diffracted from
aperture, understand Fraunhoffer and Fresnel Diffraction.
In the laboratory course, student will gain hands-on experience of using various optical
instruments and making finer measurements of wavelength of light using Newton Rings
experiment, Fresnel Biprism etc. Resolving power of optical equipment can be learnt
first hand.The motion of coupled oscillators, study of Lissajous figures and behaviour
of transverse, longitudinal waves can be learnt in this laboratory course.
Unit 1
Superposition of Two Collinear Harmonic oscillations: Simple harmonic motion (SHM).
Linearity and Superposition Principle. (1) Oscillations having equal frequencies and (2)
Oscillations having different frequencies (Beats).
(6 Lectures)
Superposition of Two Perpendicular Harmonic Oscillations: Graphical and Analytical
Methods. Lissajous Figures (1:1 and 1:2) and their uses.
(2 Lectures)
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Unit 2
Waves Motion- General: Transverse waves on a string. Travelling and standing waves on
a string. Normal Modes of a string. Group velocity, Phase velocity. Plane waves. Spherical
waves, Wave intensity.
(8 Lectures)
Unit 3
Sound: Sound waves, production and properties. Intensity and loudness of sound. Decibels.
Intensity levels. General idea of musical notes and musical scale. Acoustics of buildings
(General idea).
(6 Lectures)
Unit 4
Wave Optics: Electromagnetic nature of light. Definition and Properties of wave front.
Huygens Principle. Interference: Interference: Division of amplitude and division of
wavefront. Young’s Double Slit experiment. Lloyd’s Mirror and Fresnel’s Biprism. Phase
change on reflection: Stokes’ treatment. Interference in Thin Films: parallel and wedge-
shaped films. Newton’s Rings: measurement of wavelength and refractive index.
(14 Lectures)
Unit 5
Diffraction: Fraunhofer diffraction- Single slit; Double Slit. Multiple slits and Diffraction
grating. Fresnel Diffraction: Half-period zones. Zone plate. Fresnel Diffraction pattern of a
straight edge, a slit and a wire using half-period
zone analysis.
(14 Lectures)
Unit 6
Polarization: Transverse nature of light waves. Plane polarized light – production and
analysis. Circular and elliptical polarization (General idea).
(7 Lectures)
Practical : 60 Hours
PRACTICALS- GE LAB: Waves and Optics Lab
Dedicated demonstration cum laboratory session on the construction, and use of
spectrometer and lasers, and necessary precautions during their use.
Session on experimental data analysis, theory of random errors and the standard error in the
mean. Use of error bars in graphs and errors in slope and intercept.
At least 05 experiments from the following:
1. To investigate the motion of coupled oscillators
2. To determine the Frequency of an Electrically Maintained Tuning Fork by Melde’s
Experiment and to verify λ2 – T Law.
3. To study Lissajous Figures
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4. Familiarization with Schuster`s focussing; determination of angle of prism.
5. To determine the Refractive Index of the Material of a Prism using Sodium Light.
6. To determine Dispersive Power of the Material of a Prism using Mercury Light
7. To determine the value of Cauchy Constants.
8. To determine the Resolving Power of a Prism.
9. To determine wavelength of sodium light using Fresnel Biprism.
10. To determine wavelength of sodium light using Newton’s Rings.
11. To determine the wavelength of Laser light using Diffraction of Single Slit.
12. To determine wavelength of (1) Sodium and (2) Spectral lines of the Mercury light
using plane diffraction Grating.
13. To determine the Resolving Power of a Plane Diffraction Grating. To determine the
wavelength of laser light using diffraction grating.
References for Theory :
Essential Readings :
1. Vibrations and Waves, A.P. French, 1stEd., 2003, CRC press.
2. The Physics of Waves and Oscillations, N.K. Bajaj, 1998, Tata McGraw Hill.
3. OPTICS, (2017), 6th Edition, Ajoy Ghatak, McGraw-Hill Education, New Delhi;
4. Fundamentals of Optics, F.A Jenkins and H.E White, 1976, McGraw-Hill
Additional Readings:
1. Fundamentals of Optics, A. Kumar, H.R. Gulati and D.R. Khanna, 2011, R. Chand
Publications
2. University Physics. F.W. Sears, M.W. Zemansky and H.D. Young. 13/e, 1986.
Addison-Wesley.
References for Laboratory Work:
1. Advanced Practical Physics for students, B.L.Flint and H.T.Worsnop, 1971, Asia
Publishing House.
2. Advanced level Physics Practicals, Michael Nelson and Jon M. Ogborn, 4th Edition,
reprinted 1985, Heinemann Educational Publishers
3. A Text Book of Practical Physics, Indu Prakash and Ramakrishna, 11th Edition, 2011,
Kitab Mahal, New Delhi.
4. Practical Physics, G.L. Squires, 2015, 4th Edition, Cambridge University Press
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