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Practicals
PG Practicals
Contour Integration
The basic idea of contour integration is to extend the concept of integration from the real line to the complex plane. Instead of integrating a function along a real interval, we integrate it along a path (or contour) in the complex plane. This allows us to use the properties of analytic functions and the residues of poles to evaluate integrals that would be difficult or impossible to compute using standard real analysis techniques.
JET: English-PRACTICE SET-I
PRACTICE SET-I
JET: English-Lecture-IV
Ratio
Quantum Mechanics in Momentum Space by M Lieber
By M. Lieber Received 18 June 1974
JET: English-Lecture-III
Time & Distance
Star & Delta Connection
Star (also called Wye or Y) and Delta (Δ) connections are fundamental network configurations used extensively in electrical engineering, circuit design, and power system analysis. These connections help simplify complex three-phase networks, making them easier to analyze for voltage, current, impedance, and power calculations. The star connection consists of three circuit elements whose one end is connected to a common junction known as the star point or neutral point, while the other ends form the three independent phase terminals. This configuration resembles the shape of the letter ‘Y’. It is widely used in power transmission systems, distribution networks, and balanced load connections due to its ability to provide two voltage levels—phase and line voltages.
PG-II-Practical
JET: English-Lecture-II
Number & Letter Series
Fock
On the Theory of the Hydrogen Atom
by V. Fock, Leningrad
(Received August 5, 1935)
Fock-German
Theory of the Hydrogen Atom
JET: English-Lecture-I
Number System
JET - Paper-I
These topics will be covered from the subject General Paper on Teaching & Research Aptitude (Code No. 00, Paper-I), and the reading materials can be accessed by clicking on the hyperlinks.
JET: Lecture-V
1. Scalar and Vector Potentials
JET: Lecture-IV
Integral Theorems
JET: Lecture-III
Line, Surface and Volume Integral
Resistors
Resistors: Types, Characteristics, and Colour Coding
Frame Of Reference
In the study of scattering theory, nuclear reactions, and collision processes, the distinction between the Laboratory (Lab) reference frame and the Centre-of-Mass (CM) reference frame plays a central role. These two frames provide different perspectives for describing the motion, momentum transfer, and angular distribution of interacting particles. Since observations in an experiment are made in the laboratory frame, but theoretical simplicity often arises in the centre-of-mass frame, understanding the transformation between these two coordinate systems becomes essential.
Alpha Scattering
Alpha (α) scattering refers to the interaction of alpha particles—helium nuclei consisting of two protons and two neutrons—with atomic nuclei or atoms. The study of α-scattering has played one of the most pivotal roles in the development of modern physics. Historically, Rutherford’s α-scattering experiments in 1909 led to the discovery of the atomic nucleus and gave rise to the planetary model of the atom. These experiments showed that most α-particles pass through thin metal foils with little deflection, while a very small fraction undergo large-angle scattering, revealing the presence of a compact and massive nucleus.
3D Collision
The theory of collision in three dimensions is a fundamental aspect of quantum scattering, describing how a particle interacts with a potential when motion is not restricted to a single line but occurs in full three-dimensional space. Unlike one-dimensional scattering, where the particle approaches the potential from the left or right, three-dimensional collisions require the description of wave propagation in spherical geometry. This approach is crucial in understanding atomic, nuclear, and molecular processes where interactions occur isotropically.