# Characteristic Equation

The mathematical equation whose solution defines the dynamic characteristics of the structure in terms of its natural frequencies, damping, and mode shapes.

The mathematical formulation of the characteristic equation is called the Eigenvalue problem. The characteristic equation is obtained from the equations of motion for the structure.

### Eigenvalue Problem

The mathematical formulation and solution of the characteristic equation is called the Eigenvalue problem.

**See also: **Damping, Mode Shape, Natural Frequency.

**Subjects: ** Noise & Vibration