Nuclear Recations In nuclear physics, a nuclear reaction is a process in which two nuclei or nuclear particles collide to produce products different from the initial particles. In principle a reaction can involve more than two particles colliding, but because the probability of three or more nuclei to meet at the same time at the same place is much less than for two nuclei, such an event is exceptionally rare. While the transformation is spontaneous in the case of radioactive decay, it is initiated by a particle in the case of a nuclear reaction. If the particles collide and separate without changing, the process is called an elastic collision rather than a reaction....
Nuclear Shell Model It has been found that the nuclei with proton number or neutron number equal to certain numbers 2,8,20,28,50,82 and 126 behave in a different manner when compared to other nuclei having neighboring values of Z or N. Hence these numbers are known as magic numbers. This is found to be in accordance with the observed nature of elements with filled shells. Thus Physicists looked at such a possibility in case of filling of nucleons in the nucleus. Thus a new model of nucleus has emerged. This model is known as the Shell model....
The liquid drop The liquid drop model is a model in nuclear physics which treats the nucleus as a drop of incompressible nuclear fluid, first proposed by George Gamow and developed by Niels Bohr and John Archibald Wheeler. The fluid is made of nucleons (protons and neutrons), which are held together by the strong nuclear force....
Continuum Mechanics Strain tensor  An elastic body under an applied load deforms into a new shape. As shown in the gure 1 two adducent points p and q on the body displaced to p0 and q0 by the application of the force ~F. The displacements ~u1 and ~u2 of the point p and q are...
Moving Coordinate System Moving coordinate systems are important because, no material body is at absolute rest. As we know, even galaxies are not stationary. Therefore, a coordinate frame at absolute rest is hypothetical, hypothesized by Newton, where his laws of motion hold. In reality, we have the moving frames, prime example being Earth itself. We therefore need to know how the Newton's laws operate in a moving frame like a rotating frame (e.g. Earth)....
Classical Mechanics 1 Moving coordinate systems are important because, no material body is at absolute rest. As we know, even galaxies are not stationary. Therefore, a coordinate frame at absolute rest is hypothetical, hypothesized by Newton, where his laws of motion hold. In reality, we have the moving frames, prime example being Earth itself. We therefore need to know how the Newton's laws operate in a moving frame like a rotating frame (e.g. Earth)....
Classical Mechanics 2 Constraints means restrictions; constrained motion means restricted motion. Most of the motion that we encounter, is constrained motion. Most physical realizations of constrained motion involve surfaces of other bodies, for example,...
Classical Mechanics 3 A rigid body is defined as a system of mass points subject to the holonomic constraints that the distances between all pairs of points remain constant throughout the motion....
Hamilton's equations Lagrange formulation is in terms of generalized coordinates qi and generalized velocities q_i gives equations of motion, which are second order in time. Instead if we regard N generalized coordinates qi and N generalized momenta pi as independent variables, and again q(t) and p(t) at every instant of time t, we will get 2N rst order equations. Hence the 2N equations of motion describe the behaviour of the system ina phase space whose coodinates are the 2N independent variables. These are called canonical coordinates and canonical momenta. This new formulation is by the Hamiltonian and is known as Hamiltonian formulation....
