Värähdely

Värähdely, also known as oscillation, is a repetitive variation, typically in time, that can be either in magnitude, position, or in other measures. It is a fundamental phenomenon observed in many areas of science and engineering. A simple harmonic oscillator is a system that, when displaced from its equilibrium position, experiences a restoring force proportional to the displacement. This leads to periodic motion back and forth around the equilibrium point.

Examples of vibratory phenomena are abundant. In physics, the swinging of a pendulum, the vibration of a spring-mass system, and the propagation of waves like sound and light are all forms of oscillation. In mechanical systems, vibrations can be undesirable, leading to wear and tear, noise, and structural fatigue. Therefore, vibration analysis and control are crucial in engineering design, for instance, in designing bridges, aircraft, and machinery.

The study of vibrations often involves concepts such as amplitude, frequency, period, and phase. Amplitude refers to the maximum displacement from the equilibrium position. Frequency indicates how many cycles of oscillation occur per unit of time, often measured in Hertz (Hz). The period is the time it takes to complete one full cycle. Phase describes the position of an oscillating object in its cycle at a given moment. Vibrations can be classified as free vibrations, which occur when a system is disturbed and allowed to oscillate without any external force, or forced vibrations, which occur when a system is subjected to a continuous external periodic force. Resonance is a phenomenon that occurs when the frequency of the applied force matches a natural frequency of the system, leading to a significant increase in amplitude.