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What causes resonance? Why does a vibrating object only cause another object to vibrate of the two objects have the same natural frequency?
Scheuerf said:Why does a vibrating object only cause another object to vibrate of the two objects have the same natural frequency?
It doesn't take much energy at the appropriate frequency to cause vibrations to build up in a low-loss resonant system.Scheuerf said:What causes resonance? Why does a vibrating object only cause another object to vibrate of the two objects have the same natural frequency?
A resonant device, such as a swing, acts as an energy store. You can keep giving it a small push at the right moment of every cycle, and the swing gradually builds up in amplitude. It is summing and storing the energy from all the small pushes. If there is another resonator nearby, tuned to the same frequency, only the slightest coupling between the two will, in the same way, cause the gradual transfer of energy from one to the other.Scheuerf said:What causes resonance? Why does a vibrating object only cause another object to vibrate of the two objects have the same natural frequency?
I learned long ago from "Mr. Wizard" that vibration caused by friction is due to a "slip and stick" alternation.rumborak said:the driving force does not have to be periodic at all.
Your description of the violin sounds good, but I have found that relaxation oscillators (slip and stick etc) are reluctant to be locked to a resonant circuit. Maybe this is just the experimental set up or it may be something fundamental.rumborak said:As another side comment, the driving force does not have to be periodic at all. That's how violins work: The bow scratching across the string creates essentially a noise input signal to the string, but the resonance frequency of the string gets selectively amplified.
Scheuerf said:I always hear people saying natural frequencies or a set of natural frequencies. How does an object have more than one natural frequency?
Consider two masses connected by three springs which are fastened to rigid walls and consider longitudinal displacements only. There are two natural frequencies; one where the masses are in phase and one where the masses are out of phase. Extend this idea to a continuous string consisting of atoms connected by forces that behave like springs and you have as many natural frequencies as there are atoms (in this model). Check out any 'coupled oscillators' chapter of a classical mechanics text for more detail.Scheuerf said:I always hear people saying natural frequencies or a set of natural frequencies. How does an object have more than one natural frequency?
Scheuerf said:Does that object vibrate at its own natural frequency, or the natural frequency of the object causing it to vibrate.
Resonance is a phenomenon that occurs when an object or system is subjected to a periodic force at its natural frequency. This causes the object to vibrate at a larger amplitude, resulting in a buildup of energy and a stronger response.
Some common examples of resonance in everyday life include the swinging of a pendulum, the sound produced by a tuning fork, and the vibrations in a guitar string.
Resonance can have both positive and negative effects on different objects and systems. In some cases, it can enhance the performance and efficiency of a system, while in others it can cause damage or failure.
The occurrence of resonance is influenced by several factors, including the natural frequency of the object or system, the frequency and magnitude of the external force, and the damping or resistance present in the system.
Resonance can be controlled or prevented by altering the natural frequency of the object or system, adjusting the frequency of the external force, or introducing damping mechanisms to dissipate the energy buildup. Proper design and maintenance can also help prevent resonance-related issues.