An Experiment To Find The Acoustic Impedance Of Paraffin And Water

1905 words - 8 pages

An experiment to find the acoustic impedance of paraffin and water
Abstract
The speed of sound through paraffin and water was measured, and came close to the generally expected value. The speed in was calculated as 1458.36±16.2ms^(-1) in water and 1212±23.7ms^(-1) in paraffin. Then the density of these two liquids was measured, and combined with the speed of sound to find the acoustic impedance. . The acoustic impedance of water was 1575±29kgm^(-2) s^(-1) and the acoustic impedance of paraffin was 1066.6±32kgm^(-2) s^(-1) . To check that these values were correct the reflection coefficient of a boundary between paraffin and water was calculated using the acoustic impedances of the liquid, then found by comparing the amplitudes of the transmitted and reflected waves. The values were 0.192±0.02 and 0.13±0.02, which are close enough to each other to validate that the acoustic impedances measured are quite accurate.
introduction
When a wave travelling through a material hits a boundary with another material it is affected by the boundary and some of it will be reflected back. How much is reflected back depends on the acoustic impedance of the materials at the boundary.
This experiment will find, experimentally, the acoustic impedance of paraffin and water. This will be done by measuring the density of these materials and the speed of sound through them. The values obtained for the acoustic impedance will be used to find the reflection coefficient of the boundary. This value will be checked by measuring the amplitude of reflected waves off a boundary and then finding the reflection coefficient from these measurements. If the two values obtained for the reflection coefficient are close, then the acoustic impedance measurements will be validated.
Theory
When a sound wave travelling in a liquid hits a boundary with another material, some of the wave is reflected off the boundary. The amplitude of the reflected wave is given by the equation:
R=A_R/A_I
Where R is the reflection coefficient of the boundary, A_R is the amplitude of the reflected wave and A_Iis the amplitude of the incident wave. The reflection coefficient for a particular boundary can be also found using the equation:
R=(Z_1-Z_2)/(Z_1+Z_2 )
Where Z_1 is the acoustic impedance of the material the wave is originally travelling in, and Z_2 is the acoustic impedance of the other material at the boundary. The acoustic impedance is the resistance of a material to sound propagating through it, and can be found using the equation:
Z=vρ
Where v is the speed of sound in the material, and ρ is the density of the material. The speed of the sound can be found experimentally, using the equation v=2d/t where d is the distance from the wave source to the boundary, and t is the time it takes the wave to get from the source to the boundary and back again.
Description of apparatus
The measurements of the amplitude of the reflected waves and the speed of sound in the liquids were made in...

Find Another Essay On AN EXPERIMENT TO FIND THE ACOUSTIC IMPEDANCE OF PARAFFIN AND WATER

Salt Water Battery Experiment to Determine the Conductivity of Water When Salt Was Added to The Solution

791 words - 3 pages AbstractThe purpose of choosing the salt water battery as my experiment was to determine the conductivity of water when salt was added to the solution. During the experiment I determined that when salt was added to the water, the voltage decreases slower every time more salt was added. To get these results a jar was filled with bottled water and was attached with one zinc coated nail and a copper coated wire to a voltmeter to measure the voltage

Physics of the Acoustic Guitar Essay

2039 words - 8 pages styles and designs for acoustic guitars, but no matter the style, all of them have essentially the same parts. The body acts as an anchor for the neck and bridge. The top of the body is called the sounding board. It is responsible for almost all of the guitars acoustics, and is what allows the ear to hear the sound created by playing the guitar. The sounding board generally has a large hole cut in it called the sound hole. The bridge

This is an experiment on how planaria regenerate body parts and an explaination as to how the experiment was performed.

1473 words - 6 pages system. When two flatworms join, each exchanges sperm and fertilizes the other's eggs. Their simple body plan also allows them to regenerate complete bodies from mere fragments by asexual reproduction. Their body plan consist of a simple nervous system that includes a primitive brain, central nervous system, muscles, an internal reproductive system, intestines and an excretory system that includes specialized flame cells. In this experiment, a

Water of crystallization Aim:<Tab/>Prepare a standard solution of hydrated sodium borate to find the number of moles of water of crystallisation

1145 words - 5 pages measured hydrated sodium borate to the 250 cm3 beaker then find the mass of the weighing bottle once again to see how much of the compound was actually movedAdd small amounts of distilled water into the beaker while constantly stirring the water with the stirring rod and crushing the compound with the rubber end. Repeat until compound is fully dissolved (make sure the solution does not rise over 250cm3)Rinse the volumetric flask with distilled water

"Life Story", which is an essay about the race to find the structure and function of the DNA macromolecule.

2428 words - 10 pages The hunt for where life comes from and what life consists of involved many different personalities, places, and events that came together to reveal an answer that had particularly become of interest in the years preceding the discovery, as much of the world tried to move away from death and closer to life. In 1953, James Watson and Francis Crick presented the structure and function of the nucleic acid DNA, the macromolecule found in living

An experiment to look at the effect of 1 factor on an enzyme

1586 words - 6 pages AimTo design and carry out an experiment to look at one factor which affects the enzyme catalase.Catalase is involved in the breakdown of Hydrogen Peroxide into water and oxygen.2H202 "_ 2H20 + 02It can be found in most cells, however it is mostly concentrated in the liver, kidney and tuber cells of plants (e.g. potato).HypothesisI predict that as the temperature increases the oxygen produced will increase until a point (optimum temperature

I have been asked to investigate how the temperature of an experiment

1094 words - 4 pages Precautions: · Wear goggles when using acid · Don't boil the acid · Don't mess with the acid Fair Test: I made this a fair test firstly by making sure I had exactly 5g of marble chips and 50ml of hydrochloric acid each time I did the experiment. I also made sure the water in the cylinder was full to the top when I tipped it up into the bowl and none came out. When I put the acid in, I made sure the bung was on properly so no gas

Who is an educator ? A comparison between Aristophanes' "Clouds" and Plato's "Apology" to find an answer to the question.

1101 words - 4 pages Who is an educator? How and what he/she can teach someone for the development of responsible citizenship?With regard the questions above there will be comparisons of the texts, Plato's Apology and Aristophanes' Clouds.In Apology, at passage 20 b Socrates inquires being a teacher; " But seeing that they are human beings whom do you intend to get as their instructor? Who is the expert in perfecting the human and social qualities? I assume from the

Research Experiment Examining the Effect of Caffeine on the Heart Rate of Water Fleas

819 words - 3 pages tell if any of my results are anomalous, meaning that the average of my results is not taking lots of repeats into account and may be seriously influenced by an unnoticed anomalous result. If I were to carry out this experiment I would try to ensure I would have more time and I would try to work quicker, as I would know better what I was doing. This is because I did not have enough time to test all the different caffeine strengths I wanted to, or to carry out enough repeats. Each repeat took so long as many of the fleas we were to test on were already dead, so it was very hard to find a living one to test on.

A Study of the Operations Management at HOLLY FARM- an icecream manufacturing company. We were required to find the feasibility of expanding teh facilities and production processes.

3659 words - 15 pages for the business there. In the last part; 'Recommendations and Action Plan', I will show a recommended alternative strategy for the business and several solutions for alleviating its constraints.2. Evaluation of Current Operations and Gillian's Business Strategy2.1 Gillian's Aims and Objectives2.1.1 Sales ForecastAccording to Gillian's forecasts, while there will be an increase in farm shop sales by 50%, there will be a decline in retail shops

EXPERIMENT: Effect of Dissolved Carbon Dioxide on the pH of water

1686 words - 7 pages metals will dissolve more readily which will make them even more toxic. When pH is high, ammonium in water is changed to toxic ammonia.)) 2Hypothesis:The dissolved Carbon Dioxide will cause the pH of water to decrease.Risk Assessment:While conducting this experiment a few safety precautions must be taken in order to prevent any damage to equipment or injuries. Also anything that poses a danger must be dealt with immediately. Some of the hazards and

Similar Essays

The Reactivity Of Metals. This Report Give An Experiment Showing How To Find The Most To Least Reactive Metal.

1793 words - 7 pages reacted in all the mediums tested. It was most reactive in the Dilute Hydrochloric Acid and the Water. In water, Calcium started to fizz up and rise to the surface of the water. Calcium was the only metal to react in water. In Hydrochloric Acid it also had fizzed up but turned the acid to a murky, non-transparent colour. The pop test proved that Hydrogen gas was produced. This was a Chemical Change. In the experiment of testing Calcium in oxygen

An Experiment To Find Out If The Emotional Fluctuation Was Reflected In Biological Responses.

2663 words - 11 pages AbstractThe experiment was to find out if the emotional fluctuation was reflected in biological responses. Galvanic skin conductance, pulse and inter beat interval was used as indicators to measure the emotional fluctuation of the subject. These informations were pick up by a computer through applying electrodes to the experimental subject. It was found that the actual statistical outcome did match with the expected outcome; there was a

Physics Of An Acoustic Guitar Essay

1731 words - 7 pages Physics of an Acoustic Guitar I have been watching my husband play the guitar in a band for five years and he has made it look so easy to make such beautiful music. Most guitar players have progressed with the technology of electric guitars, but when my husband picks up an acoustic guitar and starts to play a song for just me, I hear his love for me in the sounds that he produces. Imagine my surprise when a physics class conveyed to me

Investigate And Find The Relationship Between Heat Loss (Of Water) And Surface Area To Volume Ratio Of Animals.

1083 words - 4 pages To investigate the relationship between surface area : volume ratio and heat loss.INTRODUCTION:The aim of this experiment is to investigate and find the relationship between heat loss (of water) and surface area to volume ratio of animals. To investigate this, we are going to use three flasks of different volume (as the equivalent the animals) and thus different surface areas filled with water.BACKGROUND:Surface Area : Volume RatiosWe will be