The aim of this essay is to discuss what sound is. Based on my research I will be discussing what sound is, the physical and perceptual properties of sound, how sound is produced and how sound is measured. Sound is a crucial part of our everyday lives. Living in a world without sound is almost unimaginable. The organ of the body responsible for the perception of sound in the ears. A sound is a form of energy. According to Rumsey and McCormick 2005 sound is a vibrating source produced when an object vibrates and causes the air around it to move. Sound waves can travel through compressible mediums such as water air and solids. As sound moves from molecule to molecule it spreads out in all directions. The further the sound waves the weaker the sound. When sound bounces it is called an echo. According to Ellinger 2014, there are six basic physical properties of sound. These include frequency which can also be referred to as pitch amplitude or loudness spectrum or timbre location duration and envelope. Pitch is the highness or lowness of a tone or voice. Ballora 2006 lets us know that pitch and frequency are related even though they are not equivalent. When one changes the other will change in the same direction. According to Mott 2014 frequencies are grouped as low bass sound in the low-end area mid sound in the midrange and high treble sound in the high-end area.
The X-ray diffraction patterns for all composite samples of 100 x YBa2Cu3O7 δ x Ni where x 0 1 2 5 5 7 5 10 15 wt were analyzed and shown in Figure 2 a. From it one can easily see a predominant phase perovskite structure YBCO with orthorhombic Pmmm symmetry. Growing peaks of NiO monoclinic phase with unobservable impurity peaks are founded as well The intensities at 001 200 and 111 planes of NiO increase gradually with an increase of the addition of Ni, In other words, more numbers of diffraction is coming from the displayed planes as shown in Figure 2 b. This indicates the agglomerations or segregations of large quantities of Ni in the form of NiO into patches or dots. The lattice parameters a b and c were calculated using the least square method through d value and hkl planes for orthorhombic unit cell structure and tabulated in Table 1. The analysis of the XRD data indicates the presence of orthorhombic peaks of YBCO in all composites samples with different lattice constants. From the data one can observe the distortions in the orthorhombic unit cell of YBCO.
A series of superconducting composite YBa2Cu3O7 δ x Ni metal x 1 2 5 5 7 5 10 and 15 wt were prepared by the solid-state reaction method. Density and molar volume was determined using the immersion method X rays diffraction. XRD and scanning electron microscope SEM characterization were terminated for structural and microstructural analysis. The results showed the presence of orthorhombic peaks of YBCO in the whole composite samples with different lattice constants and how Ni addition affects the distortions in the orthorhombic unit cell of YBCO. A new technique has been used to measure the ultrasonic wave velocities longitudinal and transverse at 4 MHz ultrasonic frequency at room temperature. The mechanical parameters of the samples including longitudinal modulus shear modulus. Young’s modulus, Poisson’s ratio, and microhardness have been investigated from the viewpoint of the porosity and the connectivity between the formed phases.
