Resonance is a phenomenon that occurs when a system is able to oscillate with greater amplitude at specific frequencies, known as its natural frequencies or resonant frequencies. At these frequencies, even small periodic driving forces can produce large oscillations, because the energy input from the driving force is in sync with the natural frequency of the system.
Orbital resonance occurs when two orbiting bodies exert regular, periodic gravitational influence on each other due to their orbital frequencies being related by a ratio of small integers. This situation can lead to significant effects on their orbits, including stabilization or destabilization, changes in orbital shape, and alterations in orbital inclination. In a simple example of orbital resonance, if one object completes two orbits in the same time that another object completes one orbit, they are said to be in a 2:1 resonance.
Mechanical resonance is a phenomenon that occurs when a mechanical system is subjected to oscillatory forces at a frequency close to its natural frequency, leading to large amplitude oscillations. Every physical system has a natural frequency at which it tends to oscillate if disturbed. When an external force is applied at or near this frequency, it can cause the system to resonate, resulting in increased vibration levels.
The term "resonator" can refer to different concepts depending on the context: 1. **Physics and Engineering**: In a general sense, a resonator is a system that naturally oscillates at particular frequencies, known as resonance frequencies. This can occur in mechanical systems, electrical circuits, or acoustic systems. Examples include: - **Mechanical Resonators**: Such as a tuning fork or a guitar string, which vibrate at certain frequencies.
Sympathetic resonance is a phenomenon that occurs when an object or system vibrates at the same frequency as another object or system due to an external stimulus, often in the form of sound waves or mechanical vibrations. When one object is made to vibrate, it can induce vibrations in a nearby object that has a compatible frequency. This process happens because the energy from the inducing object transfers to the resonating object, causing it to vibrate in sympathy.
A Tuned Mass Damper (TMD) is a mechanical device used to reduce the amplitude of mechanical vibrations in structures, such as buildings or bridges. It consists of a mass that is suspended or mounted on a spring/damper system, which is specifically designed to counteract the vibrations produced by external forces, such as wind, seismic activity, or operational loads.
Wolf tone refers to an unpleasant, beating sound that can occur when a musical instrument, particularly string instruments like violins, cellos, or pianos, produces certain pitches that resonate in a way that interferes with other frequencies. This resonance can create a dissonant response that some musicians find harsh or undesirable.
Articles by others on the same topic
Examples:
- mechanical resonance, notably:
- pipe instruments
- electronic oscillators, notably:
- LC oscillator, and notably the lossy version RLC circuit
Perhaps a key insight of resonance is that the reonant any lossy system tends to look like the resonance frequency quite quickly even if the initial condition is not the resonant condition itself, because everything that is not the resonant frequency interferes destructively and becomes noise. Some examples of that:
- striking a bell or drum can be modelled by applying an impuse to the system
- playing a pipe instrument comes down to blowing a piece that vibrates randomly, and then leads the pipe to vibrate mostly in the resonant frequency. Likely the same applies to bowed string instruments, the bow must be creating a random vibration.
- playing a plucked string instrument comes down to initializing the system to an triangular wave form and then letting it evolve. TODO find a simulation of that!
Another cool aspect of resonance is that it was kind of the motivation for de Broglie hypothesis, as de Broglie was kind of thinking that electroncs might show discrete jumps on atomic spectra because of constructive interference.