Search results
Results from the WOW.Com Content Network
This space-dependence is called a normal mode. Usually, for problems with continuous dependence on (x, y, z) there is no single or finite number of normal modes, but there are infinitely many normal modes. If the problem is bounded (i.e. it is defined on a finite section of space) there are countably many normal modes (usually numbered n = 1, 2 ...
The goal of modal analysis in structural mechanics is to determine the natural mode shapes and frequencies of an object or structure during free vibration.It is common to use the finite element method (FEM) to perform this analysis because, like other calculations using the FEM, the object being analyzed can have arbitrary shape and the results of the calculations are acceptable.
The equation for () has solutions which exponentially grow or decay for >, are linear or constant for = and are periodic for <. Physically it is expected that a solution to the problem of a vibrating drum head will be oscillatory in time, and this leaves only the third case, K < 0 , {\displaystyle K<0,} so we choose K = − λ 2 {\displaystyle ...
Boundary value problems are similar to initial value problems.A boundary value problem has conditions specified at the extremes ("boundaries") of the independent variable in the equation whereas an initial value problem has all of the conditions specified at the same value of the independent variable (and that value is at the lower boundary of the domain, thus the term "initial" value).
The three-body problem is a special case of the n-body problem, which describes how n objects move under one of the physical forces, such as gravity. These problems have a global analytical solution in the form of a convergent power series, as was proven by Karl F. Sundman for n = 3 and by Qiudong Wang for n > 3 (see n-body problem for details
Mode conversion occurs when a wave encounters an interface between materials of different impedances and the incident angle is not normal to the interface. [1] Thus, for example, if a longitudinal wave from a fluid (e.g., water or air) strikes a solid (e.g., steel plate), it is usually refracted and reflected as a function of the angle of incidence, but if some of the energy causes particle ...
These equations provide a rigorous solution of Maxwell's equations in a linear medium, the only limitation being the finite number of modes. When there is a change in the structure along the z-direction, the coupling between the different input and output modes can be obtained in the form of a scattering matrix.
Examples of the kinds of solutions that are found perturbatively include the solution of the equation of motion (e.g., the trajectory of a particle), the statistical average of some physical quantity (e.g., average magnetization), and the ground state energy of a quantum mechanical problem. Examples of exactly solvable problems that can be used ...