Gravity- Gravity is the one of the weakest forces in the universe. It is important in astronomy. It was defined by Newton, and it was also reassured by Einstein. Gravity is the natural force between two objects. These two objects that make up magnitude and the gravitational force are the masses and the separation distance between them. One of the examples is the force doubles in size when the masses increase. The force grows less dense then what is was before. Since the two objects grow more and more apart the objects decrease in the mass. When you triple the mass the force it is only one ninth as strong then it was before.
Sounds are different in how loud they can be and how soft they can be. The more energy you put into the wave the more loudly it seems. The amplitude and the height of the sound is measured in the amount of energy in the sound wave. So when you increase the intensity of the sound everything else increases with it. The pitch and how loud it is are two different sounds. Another way to measure it is by the quality.
Later, in 1915, Albert Einstein published the general theory of relativity, in which gravity is not a force but it is a consequence of the curvature of space-time. Thus, massive body creates a curve in the space-time then inertial trajectory that was straight lines became curved. These inertial trajectories are called geodesics. An object can inertial follow a geodesic without an interaction of forces. As consequence, heavy objects create a “big” curvature on space-time that makes other object fall towards them by a geodesic. If an object has extremely big mass even the light will suffer a noticeable deflection. This object is called of black hole.Sound is a vibration or wave of air molecules caused by the motion of an object. The wave is a compression wave where the density of the molecules is higher. This wave travels through the air at a speed dependent on the temperature. A sound wave contains energy, which in turn means it can make things move. However, if the wave strikes something solid, the wave will bounce back -- an echo. Sound energy can be changed into other forms of energy, e.g. electrical energy, and vice avers; this is one of its properties that allow us to communicate by telephone.
The speculation that sound is a wave phenomenon grew out of observations of water waves. The rudimentary notion of a wave is an oscillatory disturbance that moves away from some source and transports no discernible amount of matter over large distances of propagation. The possibility that sound exhibits analogous behavior was emphasized, for example, by the Greek philosopher Chrysalis the Roman architect and engineer Vesuvius and by the Roman philosopher Boethius The wave interpretation was also consistent with Aristotle's statement to the effect that air motion is generated by a source, "thrusting forward in like manner the adjoining air, to that the sound travels unaltered in quality as far as the disturbance of the air manages to reach." Sound, a mechanical disturbance from a state of equilibrium that propagates through an elastic material medium. A purely subjective definition of sound is also possible, as that which is perceived by the ear, but such a definition is not particularly illuminating and is unduly restrictive, for it is useful to speak of sounds that cannot be heard by the human ear, such as those that are produced by dog whistles or by sonar equipment.
Sound waves are a series of longitudinal or compression waves that move through air or other materials. However, sound doesn't travel through vacuums. Sound waves are created by the vibration of an object, like the strings on a violin. Sound is about 4 times faster in liquids than in solids. It is also faster in higher temperatures than in lower temperatures. However, temperature and structure aren't the only things that effect the speed of sound The substance of a medium that sound goes through is the main cause for it to slow down/get faster. For example, if you set up two drums,one of them facing a steel wall and the other facing nothing but air the sound of the drum facing the steel wall will be much faster than the one facing nothing. The temperature and structure only have minor effects on the speed of sound.
Waves may be graphed as a function of time or distance. A single frequency wave will appear as a sine wave in either case. From the distance graph the wavelength may be determined. From the time graph, the period and the frequency can be obtained. The wave resulting from the superposition of two similar-frequency waves has a frequency that is the average of the two. This wave fluctuates in amplitude, or beats, with a frequency called the beat frequency. We can determine the beat frequency mathematically by adding two waves together. One can also measure the beat frequency directly. When you hear a beat coming from two discordant sounds you can count the number of beats per second. The number of beats per second, or the beat frequency, shows the difference in frequency between the two notes. Musicians often use this phenomena to ensure that two notes are in tune.
As a sound wave moves through a medium, each particle of the medium vibrates at the same frequency. This is sensible since each particle vibrates due to the motion of its nearest neighbor. The first particle of the medium begins vibrating, at say 500 Hz, and begins to set the second particle into gravitational motion at the same frequency of 500 Hz. The second particle begins vibrating at 500 Hz and thus sets the third particle of the medium into gravitational motion at 500 Hz. The process continues throughout the medium; each particle vibrates at the same frequency. And of course the frequency at which each particle vibrates is the same as the frequency of the original source of the sound wave. Subsequently, a guitar string vibrating at 500 Hz will set the air particles in the room vibrating at the same frequency of 500 Hz, which carries a sound signal to the ear of a listener, which is detected as a 500 Hz sound wave.The back-and-forth vibration motion of the particles of the medium would not be the only observable phenomenon occurring at a given frequency. Since a sound wave is a pressure wave, a detector could be used to detect oscillations in pressure from a high pressure to a low pressure and back to a high pressure. As the compression and rarefaction move through the medium, they would reach the detector at a given frequency.
For example, a compression would reach the detector 500 times per second if the frequency of the wave were 500 Hz. Similarly, a rarefaction would reach the detector 500 times per second if the frequency of the wave were 500 Hz. The frequency of a sound wave not only refers to the number of back-and-forth vibrations of the particles per unit of time, but also refers to the number of compression or rarefaction that pass a given point per unit of time. A detector could be used to detect the frequency of these pressure oscillations over a given period of time.
Frequency is simply the reciprocal of the period. For this reason, a sound wave with a high frequency would correspond to a pressure time plot with a small period - that is, a plot corresponding to a small amount of time between successive high pressure points. Conversely, a sound wave with a low frequency would correspond to a pressure time plot with a large period - that is, a plot corresponding to a large amount of time between successive high pressure points. The diagram below shows two pressure-time plots, one corresponding to a high frequency and the other to a low frequency.
"Scientific Background." Scientific Background. 05 Mar. 2014 <http://btc.montana.edu/ceres/html/Weight/weightbackground.htm>
"Sound Waves." Sound Waves. 10 Mar. 2014 <http://www.fi.edu/fellows/fellow2/apr99/soundvib.html>.