Velocity of Sound Experiment

Velocity of Sound Experiment Experiment no. 7: Velocity of Sound Laboratory Report Von Dela Rosa, Anna De Vera, Tricia Desierto, Department of Biological Science College of Science, University of Santo Tomas EspanÃÅ'Æ’a, Manila, Philippines Abstract Three activities were done in the experiment to demonstrate and further analyze the velocity of sound. In the first activity, the velocity of sound in air and in glass tube was computed. In the second activity, the speed of sound was computed using vernier microphone connected to vernier logger pro. Lastly, the speed of sound in solid using Kundts tube was calculated. In the data, it has been found out that the speed of sound in air has a theoretical speed of 347.8 m/s. A percent error of 7.4%, and 10.16% were acquired in the first experiment using different frequencies, and 5.66% error was acquired in the second activity. Lastly, it has been found out that the speed of sound in solid rod is computed to be 5044.33 m/s with a percent error of 15.33% when done experimentally. I. Introduction The pressure disturbance travelling from one particle to another connotes to the velocity of sound[1]. Basically, a sound wave is a travelling disturbance. Wave pulse connotes to a single disturbance while wave train is the series of disturbances. Wave frequency measures the number of pulse have been made in a length of given time[1]. In the simplest sense, frequency is the number of vibrations per seconds. It is usually measured in Hertz(Hz). On the other hand, resonance is the natural vibration frequency of an object. In the experiment, three activities have been done in  order to exemplify the different properties of sound. The objectives of the experiment are: a.) to verify the relationship between frequency of sound and its wavelength b.) to determine the speed of sound by means of a resonating air column; and c.) to determine the velocity of sound in a solid using a vibrating rod. II. Theory Sound wave Sound wave is a disturbance that travels from one location to another location. It is propagated by vibrating objects and can be transmitted through liquid, plasma, or gases as a longitudinal waves though in solids, sound waves can be transmitted as a longitudinal wave or transverse wave[1]. Longitudinal wave is a kind of wave wherein the particles move in a parallel direction relative to the wave direction. On the other hand, transverse wave vibrate perpendicular to the direction of wave motion. Frequency Frequency is defined as the number of waves per unit of time. Frequency can be computed by dividing the velocity of sound in air to the twice the mean distance of two nodes[2]. V= Theoretical Value of the speed of sound in air à °Ã‚ Ã…“† = Twice the average of the distances between two consecutive displacement nodes Equation 1. Frequency of a Sound Resonating Air Column The basic principle behind the cylindrical air column is that resonance waves will only be produced at a definite frequency[3]. The closed end of the column depicts the wave node and the open end is the antinode. If the frequency of the column is equal to the frequency of the tuning fork, achieving resonance, the intensity of the sound is increased. Therefore, if the frequency of the tuning fork is not equal to the frequency of the column, resonance will not occur and the sound will be faint[2]. L=distance between a point and the top of the glass tube D= Diameter of the resonance tube Equation 2. Equation for wavelength f= Frequency = wavelength Equation 3. Equation for Velocity of sound in air inside the glass tube t= Temperature Equation 4. Equation for speed of sound in air at a certain temperature Kundt’s tube apparatus Kundts tube is an apparatus allows the group to calculate the speed of sound. Sound waves can travel to the tube by rubbing the metal end which will create a squeaking sound. In that scenario, the vibration of the rod will vibrate the disk causing it to propagate the frequency of the rod to the glass tube. Thus, the air inside the tube will move in response to the sound waves. Fine sand will take note of the airs response to the sound wave by exposing the striations done by rubbing the metal end[3]. The antinode, and the node were then noted. The wavelength of sound is twice the length of the rod. Equation for the speed of sound in the rod is shown in Equation5. The Equation for the theoretical speed of sound in the rod is shown in Equation 6. f= Frequency R= Wavelength of sound in the rod Equation5.Speed of sound in solid Y= Young’s modulus Ï = Density of the rod Equation 6. Theoretical speed of sound in the rod III. Methodology The materials used are resonance tube apparatus, two tuning forks with different frequencies, meter stick, rubber mallet, thermometer, and Kundt’s tube apparatus. Activity 1: Resonating Air Column Starting with the water near the top of the resonance tube apparatus, the group had strike the tuning fork using a rubber mallet and placed it on top of the glass tube. The water level was lowered slowly until the loudest sound was heard. The water level was marked at the highest sound heard. After that, the distance between that point and the top of glass tube was measured. Also, the diameter of the resonance tube was also measured. The wavelength of the sound produced was calculated. Two trials have been done to determine the average wavelength. Using the average wavelength and frequency engraved, the velocity of the sound in air was computed. The temperature of air inside the glass tube was also determined without the thermometer touching the water. The speed of sound in air was computed using the noted temperature. The percent error was computed by comparing the speed using the average wavelength and frequency and the speed calculated using the temperature inside the tube. The pr ocedure was computed using other tuning forks. Activity 2: Speed of Sound The vernier microphone was connected to Channel 1 of the interface. The position of the microphone was placed near the open end of a closed tube. The file 24 Speed of Sound in Physics was opened. As soon as the data collection begins, the fingers were snapped near the tube. From the graph in the computer screen, te time interval between the start of the first vibration and start of echo was determined. That time was noted as the time interval for the sound to travel through tube and back. The speed of sound was computed by dividing the length of the tube by one-half of the time interval obtained from the graph. The percent error was computed with the accepted value obtained in the first activity. Activity 3: Speed of Sound in Solid A thin layer of cork dust was placed uniformly in the Kundts tube. The rod was clamped at the center. The rod was rubbed with a piece of cloth with coarse powder, setting the rod into vibration producing high frequency. The wave pattern will be formed in the cork dust inside the glass tube. The displacement of the two consecutive displacement nodes has been measured and the mean distanced of the distance was calculated. The frequency of the sound was also calculated. The speed of sound in the rod and the theoretical speed of sound in the rod were also computed. Lastly, the percent error was calculated using the computed data. VI. Results and Discussion The three activities that were done in this experiment elaborating the speed of sound as it travels along a path. Activity 1: Resonating Air Column Temperature of air: 280C Diameter of Resonance Tube= 0.0344 m Table 1A: Measurements of Wavelengths Table 1A shows the frequency of the Tuning Fork and the different wavelengths of the three trials in meters. The result of the wavelength of each trials means that these are the wavelengths where the members heard the loudest sound that the Tuning Fork produced. Table 1B: Calculated Quantities Table 1B shows the computed Average Wavelengths in unit of meters; the Experimental and Theoretical Speeds both in unit of meters per second; and their respective % errors. Activity 2: Speed of Sound Table 2: Speed of Sound Table 2 shows the Total and Average Travel Times of both trials in unit of seconds; the Experimental and Theoretical Speeds that were calculated in unit of meters per second; and the computed % error of 5.66%. Figure 1: Trial 1 Figure 2: Trial 2 Figures 1 and 2 shows the different Time Interval of trials 1 and 2, between the start of the first vibration and the start of the echo vibration. Activity 3: Speed of Sound in Solid Table 3: Speed of Sound in Solid Table 3 shows the Average distances between node to node in meters; the wavelength of sound in air in meters per second; the frequency of sound in hertz; the length of the rod and the wavelength of sound in rod both in unit of meters, the wavelength of sound in the rod is twice the length of the rod; the experimental and theoretical speeds both in meters per second; and the computed % error of 15.33%. V. Conclusion The relationship between the frequency of sound and its wavelength was verified. In conclusion, the frequency and wavelength is inversely proportional to one another. The speed of sound was successfully determined by means of a resonating air column with percent errors of 7.4% and 10.16%. The determination of velocity of sound in a solid was successful by using a vibrating rod with a percent error of 15.33%. It can therefore be concluded that the distance between node to node is equivalent to the wavelength of sound. VI. Applications 1. What is the relation between frequency and wavelength of sound produced in a medium? The frequency and wavelength is inversely proportional to one another. The longer the wavelength, the shorter the frequency and vice versa. 2. What is the use of water in the activity 1? The water serves as reflector of sound waves back to the open end to cause a hearing sound if the frequency of the column equals to the frequency of the tuning fork. 3. In medical practice, ultrasound in the range of 1 to 5 megahertz is being used as an imaging modality, The associated wavelength in a typical human tissue range from 0.3mm to 0.06 mm. Find the velocity of ultrasound in the tissue. 4.The outer ear of a human may be thought of as closed pipe 2.7 cm long on the average. What frequency would be most effectively detected by the ear at 30 degrees Celsius. 5. Suppose that we increase the temperature of the air through which a sound wave is travelling, what effect does this have on the velocity of the wave. For a given frequency, what effect does increasing the temperature have on the wavelength of the sound wave? Explain. If the temperature increases, then the molecules are being excited. Therefore the molecules vibrate faster, causing the velocity of the wave to travel faster. Increasing the temperature corresponds to shorter sound wave. 6. If you were lying on the ground, would you hear footsteps sooner or later with your ear touching the ground or not? You would hear the footsteps sooner, because sound travels faster in a solid medium than in air. References: [1]  Pitch and frequency. (n.d.). Retrieved May 9, 2014, from Physicsclassroom: http://www.physicsclassroom.com/class/sound/Lesson-2/Pitch-and-Frequency [2]  Ã‚  Resonant air column. (n.d.). Retrieved May 9, 2014, 2014, from hartnell: http://www.hartnell.edu/physics/labs/4c/2resonantaircolumn.pdf [3] Speed Of Sound In Thin Metal Rods And Young Modulus. (n.d.). Retrieved May 9, 2014, from dsu.nodak: http://www2.dsu.nodak.edu/users/edkluk/public_html/nslab/ls_sv_ym.html

Rape fantasies :: essays research papers

Written in 1977, "Rape Fantasies" appears to be a recap of a conversation among several women during their lunch hour, a few of them playing bridge, one--Chrissy the receptionist--reading aloud from a tabloid. When Chrissy asks the question, "How about it, girls, do you have rape fantasies?" the story unfolds with each woman's response, all retold from the perspective of Estelle, who's doing her best to deflect the entire conversation by concentrating on her bidding. The conversation is tragically ironic, moving from woman to woman, Darlene calling the entire subject "disgusting," Greta describing a Tarzan-like scenario, Chrissy describing hers in a bubble bath, when Estelle, ever the voice of reason, reminds them that what they're describing are sexual fantasies: "Listen . . . those aren't rape fantasies. I mean, you aren't getting raped, it's just some guy you haven't met formally who happens to be more attractive than Derek Cummins . . . and you have a good time. Rape is when they've got a knife or something and you don't want to" (104.) Estelle then describes her rape fantasy where she deflects her attacker by squirting juice from a plastic lemon in his eyes ("You should hear the one about the Easy Off Cleaner"), but also includes the one where "this short, ugly fellow comes up and grabs my arm . . . [and] I say, kind of disgusted, 'Oh for Chrissake,' and he starts to cry," which prompts a wave of sympathy in Estelle (106). And there are more, each with Estelle warding off her attacker through outsmarting him ("I've just found out I have leukemia"), or talking him out of it. As the narrative continues, the reader becomes aware that Estelle is addressing someone in addition to the reader--"I hope you don't mind me holding my nose like this . . ." (107) and that person is probably a man (twice Estelle says, "But I guess it's different for a guy"). As the story ends, we realize that Estelle all along has been in a bar, speaking to a man she has just met, worrying about the possibility she will be raped by him. "Like, how could a fellow do that to a person he's just had a long conversation with, once you let them know you're human, you have a life too, I don't see how they could go ahead with it, right?

More and More on Technology Essay

They are the ‘machines’ which just receive their leaders’ requirements and relying on machines to complete without thinking. Becoming shortsighted and lose their belief, human act just for only financial purpose, regarding the progress and the negative effects. There have been many crises appearing one by one at the aspect of environmental pollution, religious conflicts and the injustice in the social wealth. For example, the Rhine has lost the beauty described by Friedrich HÃ ¶lderlin, a major German lyric poet, and been forced to be cut off and be a hydropower station to produce electricity as a slave to sever for human. Nature has changed its role, losing its previous holy, and become a serious of progress of being exploded, transformation, storage and distribution. There is not anybody like the Indians in New Mexico, refusing to use steel plough to tillage. Why? Is it just a rejection of using the plough? It’s absolutely not. At the aspect of Indians, land is their mother and they should respect and protect her as a part of their bodies and using the steel plough to cultivate the land equals to doing harm to their mother. Itis not a foolish behavior. In contrast,it completely shows they still have the loyalty and the pure soul comparing with those numb people lost in the frigid material world. What’s more, human are just rescued by technology but lose in their own dilemma created by themselves. For women, suffering from the twisted complex ethics and aesthetics, they are on the heavier social pressure of every behavior given by the followed medium. Even the weight, the figure and the action of the every part of their body are strictly required and involved in their ethics. They have to limit their desire to make the body slim and the culture of blind diet and losing weight, causing women live in a nervous station and get psychological disease. To sum up, technology, different from machine, is a dynamic progress where human use machine system to communicate with the nature to balance the relative relationships. It is a positive product of human exploring the objective world but human cannot rely on to seriously. Though most of people are the user of new technology and not the finder, our thought should not be limited by technology. We should consider how to use the technology to make the world harmonious and serve human more effectively.

The Letter Z Will Be Removed from the English Alphabet

The Letter Z Will Be Removed from the English Alphabet The Letter Z Will Be Removed from the English Alphabet The Letter Z Will Be Removed from the English Alphabet By Guest Author Surprising as it sounds, it looks like the English alphabet will be losing one of its letters on June 1st. The announcement came from the English Language Central Commission (ELCC). Here is a quote from the press release: After carefully considering and debating the matter for over two years, the ELCC came to the conclusion that the letter Z should be removed from the English alphabet. The main objective of this change is to simplify the phonetic aspect of the language, and to unify the American and British spellings. What will happen to the words that have the letter z in them? It depends on the word. According to the ELCC, words that started with a z will now start with an x. Examples include: zero becomes xero zoo becomes xoo zone becomes xone zodiac becomes xodiac Words that featured a z with the s sound, on the other hand, will now be officially written with the s (i.e., unifying the American and British spelling). Examples include: visualize becomes visualise analyze becomes analyse materialize becomes materialise What do you think about this change? Will it really simplify the English language, or will it make things more confusing? This post is an April fools prank. Want to improve your English in five minutes a day? Get a subscription and start receiving our writing tips and exercises daily! Keep learning! Browse the General category, check our popular posts, or choose a related post below:The Royal Order of Adjectives Abstract Nouns from AdjectivesPassed vs Past

Roman Imperial Succession in the Julio-Claudian Era

Roman Imperial Succession in the Julio-Claudian Era The Imperial period is the time of the Roman Empire. The 1st leader of the Imperial period was Augustus, who was from the  Julian  family of Rome. The next four emperors were all from his or his wifes (Claudian) family. The two family names are combined in the form   Julio-Claudian. The Julio-Claudian era covers the first few Roman emperors,  Augustus, Tiberius, Caligula, Claudius,  and  Nero.​ Ancient Roman history is divided into 3 periods: RegalRepublicanImperial Sometimes a fourth period is included: Byzantine Period. The Rules of Succession Since the Roman Empire was new at the time of the Julio-Claudians, it still had to work out issues of succession. The first emperor, Augustus, made much of the fact that he was still following the rules of the Republic, which permitted dictators. Rome hated kings, so although emperors were kings in all but name, a direct reference to the succession of the kings would have been anathema. Instead, the Romans had to work out the rules of succession as they went. They had models, like the aristocratic road to political office (cursus honorum), and, at least in the beginning, expected emperors to have illustrious ancestors. It soon became apparent that a potential emperors claim to the throne required money and military backing. Augustus Appoints a Co-Regent The senatorial class historically passed along their status to their offspring, so succession within a family was acceptable; however, Augustus lacked a son to whom to pass along his privileges. In 23 B.C., when he thought he would die, Augustus handed a ring conveying imperial power to his trusted friend and general Agrippa. Augustus recovered. Family circumstances changed. Augustus adopted Tiberius, his wifes son, in A.D. 4 and gave him proconsular and tribunician power. He married his heir to his daughter Julia. In 13, Augustus made Tiberius co-regent. When Augustus died, Tiberius already had imperial power. Conflicts could be minimized if the successor had had the opportunity to co-rule. Tiberius Two Heirs Following Augustus, the next four emperors of Rome were all related to Augustus or his wife Livia. They are referred to as Julio-Claudians. Augustus had been very popular and so Rome felt allegiance to his descendants, too. Tiberius, who had been married to Augustus daughter and was the son of Augustus third wife Julia, had not yet openly decided who would follow him when he died in A.D. 37. There were 2 possibilities: Tiberius grandson Tiberius Gemellus or the son of Germanicus. On Augustus order, Tiberius had adopted Augustus nephew Germanicus and named them equal heirs. Caligulas Illness The Praetorian Prefect, Macro, supported Caligula (Gaius) and the Senate of Rome accepted the prefects candidate. The young emperor seemed promising at first but soon suffered a serious illness from which he emerged a terror. Caligula demanded extreme honors be paid to him and otherwise humiliated the Senate. He alienated the praetorians who killed him after 4 years as emperor. Unsurprisingly, Caligula had not yet selected a successor. Claudius is Persuaded to Take the Throne Praetorians found Claudius cowering behind a curtain after they assassinated his nephew Caligula. They were in the process of ransacking the palace, but instead of killing Claudius, they recognized him as the brother of their much loved Germanicus and persuaded Claudius to take the throne. The Senate had been at work finding a new successor, too, but the praetorians, again, imposed their will. The new emperor bought the continued allegiance of the praetorian guard. One of Claudius wives, Messalina, had produced an heir known as Britannicus, but Claudius last wife, Agrippina, persuaded Claudius to adopt her sonwhom we know as Neroas heir. Nero, the Last of the Julio-Claudian Emperors Claudius died before the full inheritance had been accomplished, but Agrippina had support for her son, Nero, from the Praetorian Prefect Burrus whose troops were assured a financial bounty. The Senate again confirmed the praetorians choice of successor and so Nero became the last of the Julio-Claudian emperors. Later Successions Later emperors often designated successors or co-regents. They could also bestow the title of Caesar on their sons or other family member. When there was a gap in the dynastic rule, the new emperor had to be proclaimed either by the Senate or the army, but the consent of the other was required to make the succession legitimate. The emperor also had to be acclaimed by the people. Women were potential successors, but the first woman to rule in her own name, Empress Irene (c. 752 - August 9, 803), and alone, was after our time period. Succession Problems The first century saw 13 emperors, the 2nd, 9, but then the 3rd produced 37 (plus the 50 Michael Burger says never made it to the rolls of the historians). Generals would march on Rome where the terrified senate would declare them emperor (imperator, princeps, and augustus). Many of these emperors with nothing more than force legitimating their positions, had assassination to look forward to. Sources: A History of Rome, by M. Cary and H.H. Scullard. 1980.Also J.B. Burys History of the Later Roman Empire and The Shaping of Western Civilization: From Antiquity to the Enlightenment, by Michael Burger. For more information on imperial succession, see: The Transmission of the Powers of the Roman Emperor from the Death of Nero in A.D. 68 to That of Alexander Severus in A.D. 235, by Mason Hammond; Memoirs of the American Academy in Rome, Vol. 24, (1956), pp. 6163-133.

Hazard & Vulnerability Analysis Essay Example | Topics and Well Written Essays - 500 words

Hazard & Vulnerability Analysis - Essay Example Unlike the other phases, which focus more on short term action, the Migation Phase is all about long term planning and future foresight, which is important if you want any Emergency Management Plan to succeed. That the front end of the Migation Phase, and it what its main purpose is as the first step of the Emergency management cycle. However, the Migation Phase can also be used at the end of the cycle as a part of the Recovery Phase. But you have passed down instructions that our work is not to overlap any of the other phases, and that will put huge cracks in the cycle and utterly doom it to even working as we all hope it shall. If we are not able to work hand in hand with the Recovery Phase in helping at the tale end of problems, how are we supposed to know how to better prepare for them next time In order for a successful Migation Phase, we need it to work on both ends of the cycle, at the start and the end, and for it to work hand in hand with the Recovery phase to help better prepare ourselves for an emergency next time it may occur. Working with the other parts of the cycle are just as important if we want to be successful.

7-Eleven Japans strategic supply chain Essay Example | Topics and Well Written Essays - 1750 words

7-Eleven Japans strategic supply chain - Essay Example The success of 7-Eleven as a convenience store transformed it to become one of the world's largest operator, franchisor and licensor of convenience stores, with more than 27,900 units worldwide.In November 2005, 7-Eleven was taken private by Seven-Eleven Japan Company, a Japanese retailing chain. As the largest convenience store chain in the world, 7-Eleven convenience stores are open 24 hours a day. In Japan, the size of its stores was decreased in size that ranges from 125 to 150 square meters and each store stocks approximately 2,300 to 2,800 items. The company sells tobacco, beverages, beer, wine, candy snacks, fresh foods, dairy items and other general merchandise through its stores. In addition, 7-Eleven sells a number of private label products such as Slurpee semi-frozen carbonated beverages, Cafe Select coffee, Big Gulp fountain beverages and Big Bite hotdogs.Since its establishment in 1973, 7-Eleven Japan had taken on "Adapting to Change" as its business slogan, reflecting i ts focus on adapting to changing consumer trends. As such, its 7-Eleven convenience stores had earned the patronage of much of the population, far outstripping other companies in the convenience store sector as well as in the overall retail industry in terms of growth and profitability. In 2000, while Japan was in the midst of an economic downturn, 7-Eleven Japan opened an additional 423 stores and recorded the highest profits in the retail industry. Fact is that 7-Eleven Japan realized its phenomenal growth between the years of 1985 and 2003. During these period, the number of stores increased from 2,299 to 10,303; annual sales increased from 386 billion to 2,343 billion yen; and net income increased from 9 billion to 91.5 billion yen. Additionally, the company's return on equity (ROE) averaged around 14 percent between 2000 and 2004. In 2004, Seven-Eleven Japan represented Japan's largest retailer in terms of operating income and number of stores. Customer visits to 7-Eleven outle ts totaled 3.6 billion that year, averaging almost 30 visits to a 7-Eleven annually for every person in Japan. This impressive result and its rapid growth were due to its efforts at developing merchandise and services that met customers' needs and requirements. For example, it was the pioneer in providing ready-made meals such as sushi and spaghetti that had become popular among the Japanese population. In addition, the information and distribution systems played an especially large role in placing 7-Eleven Japan in a leading position. A convenience store chain attempts to be responsive and provide customers what they need, when they need it, where they need it. What are some different ways that a convenience store supply chain can be responsive What are some risks in each case Increasing supply chain responsiveness would mean the firm will also increase its ability to: Strategy in Increasing Supply Chain Responsiveness Risks Involved respond to wide ranges of quantities demanded meet short lead times handle a large variety of products build highly innovative products meet a very high service level Wider range of quantity implies greater variance in demand Less time to react to orders Demand per product becomes more disaggregated New products tend to have more uncertain demand Firm now has to handle unusual surges in demand Matching supply chain capabilities to customer's requirements means that a firm and their supply chain partners must be continually reassessing their performance with respect to these requirements. This reveals the importance of performance measures and their ability to relay information regarding the performance of each member within the supply chain, along with the performance of the supply chain vis--vis its end customers. Successful supply chains are those that can continue to deliver the right combination of cost, quality, and customer service as customer needs change. Weaknesses in any of these areas can mean loss of competitiveness and profits for all