“A wave is a transfer of energy from one point to another with no transfer of matter.” (Walding Et Al, 1999) Waves that require matter to propagate are referred to as mechanical waves; whereas electromagnetic waves comprise of those that do not necessitate matter to propagate. (Walding Et Al, 1999) Mechanical waves can further be divided into two sub-branches: longitudional and transverse waves. Longitudional waves occur when the particles of matter used by the wave to propogate, vibrate parallel to the direction of propogation of the wave. (Nave, 2014) Transverse waves ensue when this vibration is perpendicular to the direction of propagation as seen in figure1. (Nave, 2014)
Waves consist of many defining characteristics: wavelength, amplitude, frequency and period. The wavelength (λ) is defined as the distance from two consecutive points in the wave that are in phase. (optushome, 2014) “Amplitude (A) is the maximum vertical distance a particle is displaced from equilibrium.” (sengpielaudio, 2014) “The amount of energy carried by a wave is related to the amplitude of the wave. A high energy wave is characterized by a high amplitude; a low energy wave is characterized by a low amplitude.” (The Physics Classroom, 2014) Frequency (f) is the number of cycles of the wave pass per second and period (T) is the time required per cycle. Figure 2 illustrates these characteristics. (optushome, 2014)
The equations for frequency and period are below:
T= 1/f f= 1/T
The wave equation defines the relationship between velocity (v), frequency (f), wavelength (λ) and period (T). (The Physics Classroom, 2014) It is expressed as: v= λ/T or v= 1λ/T or v= λf
When two waves intersect, the process of interference occurs; with cons...
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...optimal levels of wave attenuation - through means of refraction and energy absorption; in regards to the formation of safe harbours and beaches.
Hypothesis
That, floating breakwaters will produce optimal levels of wave attenuation as a pose to submerged breakwaters. This is due to the floating pontoon physically coming into contact with the waves and absorbing the wave energy with part of the wave still passing under the barrier, as a pose to the submerged wave only inducing wave-break. However, if the submerged breakwater is at a height that is very close to the still water level, it will produce optimal attenuation of waves due to a large amount of energy absorption, as a pose to when the floating breakwater has a width that is relatively small compared to the wavelength. This is due to the submerged breakwater being least effective when their height is small.
walking across them. The lines and pulleys and some parts of the waves are example of
Longshore drift influences the deposition and erosion of sediments. Waves erode the coast and transport the eroded material along the coastline. Over a period of time, the material will be deposited on a beach or form a larger feature such as a spit. Groynes are structures built at equal intervals along the coastline. Their purpose is to restrict longshore drift, preventing coastal erosion.
This chapter provides some insight into pulse wave analysis and its relation to arterial diseases. The shape of the arterial pulse wave is an augmentation of the forward traveling wave with the reflected wave. The amount of wave reflection is dependent on the arterial wall properties such as arterial stiffness and is expressed in terms of Augmentation Index. This approach has been studied extensively using various measuring techniques, all of which have respective advantages and disadvantages. The purpose of PWA can be seen in the section describing the medical conditions that affect the wave shape. The discussion is included to assist the reader in understanding the purpose of pulse wave analysis.
If you put your finger gently on a loudspeaker you will feel it vibrate - if it is playing a low note loudly you can see it moving. When it moves forwards, it compresses the air next to it, which raises its pressure. Some of this air flows outwards, compressing the next layer of air. The disturbance in the air spreads out as a travelling sound wave. Ultimately this sound wave causes a very tiny vibration in your eardrum - but that's another story.
Surfers, swimmers and sunbathers use beaches for recreation. People fish off beaches for food. Since many people take their vacations at the beach, lots of beaches in tropical locations are important to their country’s economy. Entire cities, regions and countries depend on the money tourists spend while visiting the beach. Beaches are naturally very dynamic places, but people try to control them and build permanent structures, such as houses, restaurants, shops and hotels, on or near the shore. The natural erosion and deposition of beaches becomes a problem. Beaches con disappear over time, or even over night during severe storms. Beaches are areas of loose sediment (sand, gravel, cobbles) controlled by ocean processes. Most beaches have several characteristic features. First are offshore bars, which help protect beaches from erosion. Next is the foreshore, which rises from the water toward the crest of the next feature; a berm. On low-lying shores, dunes form behind beaches. Dunes look like rolling hills of sand and are blown into place by the wind. New, smaller dunes are often changing shape as the wind continues to affect them. Waves and currents move the accumulated sediment constantly creating, eroding and changing the coastlines.
Nature of wave: It is an electromagnetic wave as it does not necessarily require a medium for p...
Sound is a type of longitudinal wave that originates as the vibration of a medium (such as a person’s vocal cords or a guitar string) and travels through gases, liquids, and elastic solids as variations of pressure and density. The loudness of a sound perceived by the ear depends on the amplitude of the sound wave and is measured in decibel, while its pitch depends on it frequency measured in hertz, (Shipman-Wilson-Higgins, 2013).
Sound waves take the form of compressional waves and are caused by vibrations. Sound waves are distinguished by their speed, pitch, loudness and quality (timbre) (Lapp, 2003). There are a few parts of sound waves that we should be familiar with to better be able to understand the physics of music. The crest is the highest point of a wave, while the trough is the lowest. The wavelength of a wave is the distance between two adjacent parts of a wave, like from crest to crest, or from trough to trough....
Some physical entities such as light can display some characteristics of both particles and waves. Before the early 20th century, scientists believed that light was in the form of an electromagnetic wave. It wasn’t until the 20th century onwards that scientists found that light has properties of waves and particles. Scientists discovered different properties of light through experimentation and allowed them to determine that light actually has a wave-particle duality.
Each of the senses receives a different stimulus that allows us to perceive that specific type of information. For hearing the stimulus is sound waves. These are waves of pressure that are conducted through a medium (Martini, 2009). Often this medium is air but it can also be water or a solid object. Each wave consists of a region where the air molecules are gathered together and an opposite region where they are farther apart (Martini, 2009). A wavelength is the distance between either two wave peaks or two wave troughs. The number of waves that pass through a fixed reference point in a given time is the frequency. High pitch sounds have a high frequency where as low pitch sounds have a low frequency (Myers, 2010). The amplitude is the amount of energy, or intensity, in a sound wave. The more energy that a sound wave has, the louder it seems. For us to perceive any of the sound waves around us, they must pass through the external, middle, and inner ea...
Sir Isaac Newton is the man well known for his discoveries around the term, Motion. He came up with three basic ideas, called Newton’s three laws of motion.
Time-varying electric fields can bring magnetic fields and vice-versa. Since both fields generate each other, they occur jointly and therefore, propagate as electromagnetic waves.
Sound is essentially a wave produced by a vibrating source. This compression and rarefaction of matter will transfer to the surrounding particles, for instance air molecules. Rhythmic variations in air pressure are therefore created which are detected by the ear and perceived as sound. The frequency of a sound wave is the number of these oscillations that passes through a given point each second. It is the compression of the medium particles that actually constitute a sound wave, and which classifies it as longitudinal. As opposed to transverse waves (eg. light waves), in which case the particles move perpendicular to the direction of the wave movement, the medium particles are moving in the same or opposite direction as the wave (Russell, D. A., 1998).