1. Introduction
1.1 General Overview of Resonance and Related Fields
Resonance is a phenomenon that takes place in many areas of the physical world such as mechanics, electricity, acoustics, optics, astrophysics and nuclear physics. It is generally defined as the large response of a system to an externally applied oscillatory force at a certain frequency (called the ‘natural frequency’ or ‘resonant frequency’).
Mechanical resonance in particular occurs during simple harmonic motion. This specific type of motion is defined by two main criteria: when the displacement of the motion is proportional to the acceleration and when it is opposite in direction. This can be easily illustrated by the general equation , where is the acceleration, is a constant and x is the displacement (Tsokos 195-196).
As a system undergoes simple harmonic motion without a constant external force, its amplitude and energy will diminish naturally over time. This could be due to forces such as friction. This decrease is called damping. Damping also affects resonance: with damping, a system will only have a fraction of its amplitude at its resonant frequency. As damping gradually increases, the amplitude gradually decreases. There are different subcategories of damping. The first is under-damping, where the oscillatory motion continues but the amplitude of motion slowly decays. The second category is over-damping, where the amplitude of motion decreases to zero without oscillating. The damping explored in this paper will be active – that is, the system’s response at different frequencies will be hindered intentionally rather than naturally using different mediums, resistances and degrees of padding (“Damping”; Tsokos 207-209)
There exist many real-life ...
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... interaction between planets and asteroids. It is the phenomenon that explains the stable orbits between Neptune and Pluto, and between Jupiter and its moons. It is also an explanation for abnormally higher tides in certain bodies of water. Finally, nuclear magnetic resonance is frequently applied in magnetic resonance imaging scanners to excite atoms in the human body and produce biological images.
Resonance and damping are incredible phenomena that are present in a vast variety of scientific fields that range from the pragmatic to the obscure. Resonance is the prevailing concept in structural failures, radios, musical instruments and planetary orbits. Damping is useful in the use of vehicle suspensions, tuned mass dampers and soundproofing. The number of applications for resonance and damping will indubitably grow in the near future to serve the needs of society.
My interest in MRI started when I first read the book “MRI, The Basics” written by the author Ray Hashemi. By the time I successfully finished my MRI clinical placement in Tehran University of Medical Sciences, I knew for sure that MRI would be the field I would be choosing to take on. What attracts me most about MRI is how beautifully scientist could create a technology that can take advantage of the magnetic moments of human body for imaging it without any harms of ionizing radiation. Although there are drawbacks to MRI, combining it with other modalities would be a more effective approach to an accurate diagnosis.
This includes the introduction of the heliocentric model and the debate about pluto being a planet, that ended up changing view points on many topics.
It was proposed that if the length of the PVC pipes were to increase, then the sound produced will have a lower amplitude each time because the sound will lose energy as it continues in the pipe for a certain amount of time. However, the data actually showed that with every increase in pipe length, the amplitude got louder as well, thus refuting the hypothesis. These results made sense because what was created inside the PVC pipes was a standing still sound wave, or a resonance wave. These kinds of waves have certain locations on its wavelength in order for the change in sound to be heard, which it usually half a wavelength. With this, the tuning fork is 83.3Hz and a usual wavelength is about 300Hz, 300/83.3 = 3.6 meters, which is about 4 meters (half = 2 meters). So for the change in sound to be heard, the pipes had to be about 2 meters in change according to the frequency of the tuning
Fletcher and Rossing, The Physics of Musical Instruments (2ndEdition), Springer, New York (1998). Chapter 16 Lecture Notes on Woodwind Instruments.
Bear in mind the amplitude cannot be larger than the extension caused. by the smallest mass applied to the spring as this would not allow the
The inner workings of the turntable may seem complex at first but after reading this paper it should become clear that, like all things, the record player works on basic principals of physics. In fact, the turntable is remarkable in that the basic physical principles behind it are quite simple. Some of these will be explored here. Please enjoy your visit.
One of the most recently new advances in radiology is the use of magnetic resonance imaging (MRI). MRI has been around for the past century. It was at first called Nuclear Magnetic Resonance (NMR) and then it changed to MRI once there was an available image. Walter Gerlach and Otto Stern were the first scientists to start experimenting with the magnetic imaging. Their very first experiment was looking at the magnetic moments of silver by using some type of x-ray beam. The scientists then discovered this was by realizing that the magnetic force in the equipment and in the object itself. In 1975, the first image was finally created using and MRI machine. The scientists used a Fourier Transformation machine to reconstruct images into 2D. The first images ever use diagnostically was in 1980. This is when hospitals began to use them. At first the images took hours to develop and were only used on the patients that needed it most. Even though MRI has been around for a long time, it has advanced and has been one of the best imaging modalities recently (Geva, 2006).
The machine is a 100% accurate method of disease detection throughout the body and is most often used after other testing methods have failed to provide sufficient information to confirm a patient’s diagnosis. According to journalist Mary Bellis, two brilliant men Felix Block of Stanford University and Edward Purcell of Harvard University discovered MRI in the 1930s. Because of their discoveries they used nuclear magnetic resonance (NMR) to study composition of chem...
Sounds are produced by the vibrations of material objects, and travel as a result of
"The Physics of the Acoustic Guitar - Body." The Physics of the Acoustic Guitar - Body. N.p., n.d. Web. 26 May 2014. .
The Scholar: I think that's more a function of sound wave vibration than anything else.
Kurtus, Ron. "Overview of Sound Waves." Overview of Sound Waves . N.p., n.d. Web. 4 Apr. 2014. .
Produced sound from speakers has become so common and integrated in our daily lives it is often taken for granted. Living with inventions such as televisions, phones and radios, chances are you rarely ever have days with nothing but natural sounds. Yet, few people know the physics involved in the technology that allows us to listen to music in our living room although the band is miles away. This article will investigate and explain the physics and mechanism behind loudspeakers – both electromagnetic and electrostatic.
"Properties of sine waves." University of Manitoba. University of Manitoba, 2010. Web. 29 Nov. 2013. .