Physics and the Speed of Sound :: physics sound

The Speed of "Sound": is actually the speed of transmission of a small disturbance through a medium. The speed of sound (a) is equal to the square root of the ratio of specific heats (g) times the gas constant (R) times the absolute temperature (T). a = sqrt [g * R * T] Sonic Boom Sound generated by airflow has been around and reasearched for a long time. The increased use of fluid machines and engines has led to an increasing level of noise generation, and hence to an increasing interest in this area of research. A sonic boom is a loud noise caused by an aircraft travelling faster than the speed of sound which is mach one.. The sound propagates along the figure which is called the mach cone. The boom is due to a combination of volume and lift. While the boom due to volume can be virtually eliminated (Busemann, 1935), the boom due to lift can only be minimized. The minimum sonic boom generally does not correspond to the best aircraft. There is among others: sonic boom minimization at given drag; minimization at given volume, etc. (Seebass, 1998). Because the shock energy is nearly conserved as the shock radiates, its strength decays only slightly with the distance from the aircraft. Minimization is not straightforward, because it is constrained by structural, aerodynamic and design parameters, and not least by the variation of the thermo-dynamic properties of the atmosphere. The Speed of Sound, source: Air & Space/Smithsonian. The speed of sound varies with temperature. At sea level Mach 1 is around 742 mph. It decreases with altitude until it reaches about 661 mph at 36,000 feet, then remains at that speed in a band of steady temperature up to 60,000 feet. Because of the variation, it is possible for an airplane flying supersonic at high altitude to be slower than a subsonic flight at sea level.

Cell Phones: The Good, The Bad, and The Ugly

The prevalence of cell phones in American culture shouldn't come as much of a surprise to anyone. Cell phone use has risen In the united States from approximately 91,000 users 985 to In 2007 and n 2009 was somewhere In the neighborhood of 280,000,000, which means that approximately 90% of Americans own cell phones. And Americans arena the only ones. According to a February 2010 article on www. Cobwebs. Com, there are approximately 4. 6 billion cell phone subscriptions worldwide and that number is expected to surpass five billion by the end of the year.I had to wonder, what are the advantages and disadvantages of 90% of Americans (New York Times, May 13, 2010) and nearly 85% of the world's population using cell phones? I figure there had to be quite a few advantages for so many people to have cell phones, so I asked around. The number one answer I found was the convenience. Peoples' ability to be reached at all times, able to reach others at all times, and how fast communication with others has become. Can't reach someone by phone? Send a text. Text messages are delivered almost Instantaneously and there's no need to eave a message and Walt for a call back anymore.Many others cited having a cell phone In case of emergency. According to Pew Internet, In 2006, 74% of cell phone users reported using their cell phones in emergency situations. While cell phone bills are usually not lower than landlines bills alone, the long distance cost is significantly less for cell phone users. Long distance costs are included in the overall minute usage for most cell phone subscriptions, whereas many landlines providers charge by the minute for long distance calls. As cell phone technology advances, so o the tools available to cell phone users.A growing number of users report using their phones for such things as listening to music, checking email, keeping their daily calendars, making grocery lists, and even keeping track of daily calorie intake. (New York Times, May 13, 2010). There are many organizational tools available on the new generation of â€Å"smart phones† as well as many different navigational tools. GAPS locators In phones are subscribed to by many parents of underage cell phone users. Cell phones can also be used as cameras and video recorders and those photos and ideas are easily emailed to others or uploaded to sites such as Twitter and Faceable.Entertainment is even making the list of advantages to having a cell phone these days. As I mentioned previously, users can listen to music on their cell phones, but it doesn't stop there. Technology has advanced so much that users can now watch television shows and movies on their phones. So it seems I was correct about how many advantages must be out there, but what about the downside? The very first thought I had was about the ban on cell phones in schools and what a huge disruption cell phones must be In the classroom. That issue Is Just part of the larger issue of the widespread distract ion cell phones cause.Everywhere you go you see cell phones In use – In the coffee shop, the movie theater, the grocery store, even church, and while driving. Going back to the cost of cell phones, while heavy long distance users may notice a relief in their long distance landlines. There are costs for air time usage, text message usage, broadband usage, music purchases, games purchases, and app purchases, not to mention the dreaded overage costs. Some cell phone companies charge as much as sixty cents per minute or every minute of air time over your allotted plan.Add that to long contracts and hefty fees for canceling contracts and cell phones become quite an expensive venture. The ever-increasing technology is adding to these costs as well. Newer, smarter phones released every few months are of course attractive to users, but on top of the cost of upgrading phones on a regular basis is the added cost of the service provider's data package. In order to utilize these newer sm art phones, the data package is a requirement and on average costs something like an additional $30 ere month. Aside from financial impact, what about health impact?There seems to be quite a bit of worry over the radio frequency radiation given off by cell phones and cell phone towers. There is much argument about whether or not this sort of radiation is of any real concern, but according to www. Contemporaries. Com, there are many very serious health concerns to think about. There are reports that cell phone use can cause disturbances in sleep and concentration, fatigue, and headache. According to a BBC News report (wry. News. BBC. Co. UK), â€Å"Cell phones image key brain cells and could trigger the early onset of Alchemist's disease †¦Researchers have found that radiation from cell phone handsets damages areas of the brain associated with learning, memory and movement. † Reports linking cell phones to sterility in men, eye tissue damage, and increased chances of depr ession and cancer have also been published. In researching the negative effects of cell phones, I happened across some even more sinister effects. Take â€Å"setting† – â€Å"the act of sending, receiving, or forwarding sexually explicit messages, photos, or images via cell phone, computer, or other chital device.These messages, photos, and images are then often being further disseminated through email and internet-based social networking websites well beyond their original intended recipients. † (wry. Mass. Gob) There have been hundreds of reported cases of setting – a handful of those cases involving suicide and/or sex offense criminal charges such as child pornography in the cases involving high school students. According to www. Masc.. Com, 39% of high schools students admit to sending these types of messages and 48% say they've received them.Another very dangerous habit Americans have developed is talking on their cell phone while driving. Muff have four times the risk of being in a crash if you're on the phone while driving. † (www. Unfathomable. Com) What's even scarier are the results of a Car and Driver Magazine study that found testing while driving is much worse than driving while intoxicated. The results of this study showed that unimpaired, it took the test driver . 54 seconds to brake when indicated to do so. Add four feet to that time for legally drunk drivers, thirty six feet for drivers reading email and events feet for drivers reading a text. Http://www. Zinc. Com/id/31 545004/site/ 14081 545). According too report by the National Safety Council, 28% of accidents involve talking or testing on cell phones. I couldn't help but notice that the risks seem to outweigh the benefits considerably, but I also admit that I'm still addicted to my cell phone. There has been their use elsewhere and I think there needs to be much more, although, I'm not certain how feasible that would be to accomplish. At any rate, we all make our own choices and we all need to make smarter choices about our cell phone use.

Apple Marketing Strategy Essay

1. Apple Marketing StrategyApple has been so successful in these last years thanks to his fresh, imaginative way to think and do its business: awinning combination of exceptional products, great style and design, great strategy, innovative marketing, sleekand enticing communications.Apple owes its overwhelming success in the last years to the iPhone and to the smart iPod and iTunes productcombination, a combination of a great hardware piece with great style, great software, great performance, userfriendly interface, with a good e-business service. The iPod + iTunes halo effect and new great Mac computers andMac OS software did the rest in increasing Apple revenue stream. In the 5 years between 2003 to 2008 the Apple share value increased 25 times, from $7.5 to $180 per share. At july2008 prices, before the US Financial Crisis, Apple stock market capitalization was $160 billion.In January 2010 Apple shares topped the $210 mark.But even the best companies with the best products have bottleneck factors which often avoid full exploitation ofthe opportunities.The iPod.Few people are aware – and few market analysts too – that for the first 3 years the iPod was an absolute flop. TheiPod was launched in october 2001, and between 2001 and 2004 iPod sales were between 100-200 thousand unitsper quarter, very far from todays 10-20 million units per quarter, and the iPod sales were not even covering theproduct research & development costs. Then, in June-Aug 2004 something happened, and iPod sales began to grow strongly, quarter after quarter. Today,we all know where the iPod stands, and what a remarkable success it is.The iPod made the fortune of Apple, and it stands out as the major turning point in the company growth.Few people know that the iPod + iTunes business idea was not conceived inside Apple, but was proposed to Appleby an outside source, a music lover and Engineer named Tony Fadell.More on Tony Fadell and on the iPod marketing on iPod Marketing StrategyThe iPod marks another outstanding result in marketing:the annihilation of competitors. To know more see the analysis onThe iPod competitorsIt should be noted that, since the second generation of iPods in 2002, the iPods were made compatible not only withthe Mac operating systems but with Microsoft Windows operating systems as well.We should ask ourselves (and to Steve Jobs): how many iPods would have been sold if the iPods would had beencompatible only with Mac operating systems?Where the iPod is manufactured and assembledThe iPhone. The pipeline of new products which came out from Apple in the last years is impressive, and overwhelming. In 2007,with the successful launch of the iPhone, Apple has marked another milestone in its development and growth.And moreover, the iPhone enters a market – the market of mobile phones – a market which is mature, and saturated.Nonetheless, Apple has been able to develop a revolutionary product, and to change the paradigm in the mobile 2. Phone market.The iPhone is 5 years ahead of all its competitors. A wonderful product, amazing user interface, great design. It isnot only a mobile phone, it is a product between a mobile phone and a laptop computer. Even calling it asmartphone is not enough.In July 2008 Apple launched the second generation iPhone, the iPhone 3G.The iPhone 3GS.In June 2009 Apple launched its third generation iPhone: the iPhone 3GS.The iPhone 3GS has a 3 megapixel autofocus camera, video recording and editing capabilities, voice control, longerbattery life, 7.2 Mbps HSDPA internet connection. iPhone 3GS is twice faster than the iPhone 3G. The iPhone 3GSprices: $199 for the 16GB model, $299 for the 32GB model.more on the new iPhone 3GS on the iPhone 3GS page.More on iPhone Marketing on the iPhone Marketing Strategy page.Apple did great. no doubt. However Apple has done some serious mistakes.The most serious mistakes Apple has done concern marketing and distribution strategies in Europe.Apple has overlooked the European markets, and missing big numbers in unexploited sales. With better marketingstrategy, better communication and distribution, Apple could have made 300% more revenues in Europe in the last 4years. Apple Marketing in EuropeWe met with with Erik Stannow, Apple Vice President of Marketing for Europe & EMEA. We have been talking withErik Stannow about the marketing and distribution issues of Apple in the European markets and we gave somevaluable suggestions to improve the Apple marketing strategy and distribution in Europe.Well, it seems that in Cupertino they dont care so much about Europe.Steve JobsIf we talk about Apple success, about Apple great products, we need to talk about Steve Jobs. Steve Jobs has beenand is the great mind behind all this.Steve Jobs is a genius, he is a magician, too. He is the most skilled guy in introducing new products – â€Å"†¦ one morething† – the most skilled in presenting the key features, and he is a great communicator. Even more important, Steve Jobs has Vision. Vision in the strategy, Vision in the product development, Vision in thealliances.Apple Communication Strategy.Apple communication is sober, intriguing, simple, clear, minimalist and clever. And it has a style of its own. Both inthe tv ads, both in print ads, both in the online communications. A lesson to be learned by many companies in theworld. Well, of course when you have great products it is much easier to entice the costumers, but neverthelessdoing it with style and cleverness is a very good point. It boosts sales, but enhances the brand value too.The famous â€Å"I am a Mac, I am a PC† tv ads are a milestone in communications. Smart, simple, effective andhumiliating (for Microsoft †¦).More on Apple Communications and on the Apple Commercials â€Å"I am a Mac I am a PC† on the AppleCommunication Strategy page.

Top 5 Review Activities for Elementary Students

Top 5 Review Activities for Elementary Students Review sessions are inevitable in the classroom, and for many teachers, it can be a rather uninspiring exercise. Too often,  review activities feel boring and may leave your students feeling unengaged. But, it doesnt have to be that way. By choosing some fun and engaging activities, a traditionally mundane review session can become an active and inspiring session. Check out these five teacher-tested review lessons with your students. Graffiti Wall When students here the words its review time, you might get a bunch of groans. But, by turning the review session into a hands-on activity, students will be more likely to enjoy the exercise and even better retain the information.   Heres how it works: Place a variety of different colored dry erase markers on the front board(or different colored chalk if you have a chalkboard).Then give students a review topic, and randomly call about three to five students at a time to the board.The students goal is to think of any word that associates with the given topic.Students can write the word any way they like (sideways, up and down, backward, etc.)One rule you must enforce is that students cannot repeat any word that is on the board.Once all the students have had a turn, pair them up and have each student tell their partner about five of the words on the board.View pictures and learn more about this great  graffiti wall review activity  here. 3-2-1 Strategy The 3-2-1 review strategy is a great way for students to review just about anything in an easy and simple format. There are a few ways you can use this strategy, but often, the preferred way is to draw a pyramid. Heres how it works: Students are given a review topic and told to draw a pyramid in their notebook.Their goal is to write down three things they learned, two things they thought was interesting, and one question they still have. You can adapt this activity any way you want. Instead of asking a question on the top of the pyramid, students can write a summary sentence. Or, instead of writing two things they found interesting, they can write two vocabulary words. It is very easily adaptable.  View a picture of the 3-2-1  review pyramid. Post-It Practice If your students love the game Headbands, then they will love playing this review game. Heres what you have to do to get started. Provide each student with a Post-it note, and have them write down one review term on it.Then without the other students seeing the note, have each student choose one person to stick their note to their forehead.The goal of this activity is for students to go around the room and try to explain the term without using the actual term.Make sure that each student has the opportunity to go around the room and explain each term. Move Ahead of the Class This review game is the perfect way to incorporate teamwork while reviewing important skills. Here is how you play: Divide students into teams of two, then have students stand in a row where one student is behind one other.Use the squares of the floor as the game board and tape off a finish line.To play the game, have one person from each team face-off by answering a review question. The first person to answer it correctly moves ahead to the next square.​After the first question, the next person in line takes the place of the student who got the answer correct.The game goes on until one team crosses the finish line. Sink or Swim Sink or Swim is a fun review game that will have your students working together as a team in order to win the game. Heres what you need to know to play the game: Divide students into two teams and have them form a line and face one another.Then ask team 1 a question, and if they get it right, they can choose one person from the other team to sink.Then ask team 2 a question, and if they get the answer right, they may either sink their opponents team member or save their sunken team member.The winning team is the one with the most people at the end.

16 Fascinating Facts About Mosquitoes

16 Fascinating Facts About Mosquitoes Mosquitoes, the insects that are universally hated the world over. These pesky, disease-carrying pests make a living by sucking the blood out of just about anything that moves, including us. But take a moment to look at things from the mosquitos perspective. Mosquitoes are actually interesting  creatures. Mosquitoes Are the Deadliest Animals on Earth Take that, shark week! More deaths are associated with mosquitoes than any other animal on the planet. Mosquitoes may carry any number of deadly diseases, including malaria, dengue fever, yellow fever, Zika, and encephalitis. Mosquitoes also carry heartworm, which can be lethal to your dog. How Long Do Mosquitoes Live? An adult mosquito may live 5–6 months. Few probably make it that long, given our tendency to slap them silly when they land on us. But in the right circumstances, an adult mosquito has quite a long life expectancy, as bugs go. Most adult females live for two to three weeks. For those that winter in your garage, though- look out. Eggs can dry out for eight months and still hatch. Females Bite Humans While Males Feed on Nectar Mosquitoes mean nothing personal when they take your blood. Female mosquitoes need protein for their eggs and must take a blood meal in order to reproduce. Because males dont bear the burden of producing young, theyll avoid you completely and head for the flowers instead. When not trying to produce eggs, females are happy to stick to nectar, too. Some Mosquitoes Avoid Biting Humans Not all mosquito species feed on people. Some mosquitoes specialize on other animals and are no bother to us at all. Culiseta melanura, for example, bites birds almost exclusively and rarely bites humans. Another mosquito species,  Uranotaenia sapphirina, is known to feed on reptiles and amphibians. Mosquitoes Fly Slowly Mosquitoes average a flight speed of 1 to 1.5 miles per hour. If a race were held between all the flying insects, nearly every other contestant would beat the pokey mosquito. Butterflies, locusts, and honeybees would all finish well ahead of the skeeter. A Mosquito's Wings Beat 300–600 Times Per Second This would explain that irritating buzzing sound you hear just before a mosquito lands on you and bites. Mosquitoes Synchronize Their Wing Beats Scientists once thought that only male mosquitoes could hear the wing beats of their potential mates, but recent research on Aedes aegypti mosquitoes proved females listen for lovers, too. When the male and female meet, their buzzing synchronizes to the same speed. Salt Marsh Mosquitoes May Live100 Miles Away Most mosquitoes emerge from their watery breeding ground and stay pretty close to home. But some, like the salt marsh mosquitoes, will fly long distances to find a suitable place to live, with all the nectar and blood they could want to drink. All Mosquitoes Need Water to Breed- but Not Much Just a few inches of water is all it takes for a female to deposit her eggs. Tiny mosquito larvae develop quickly in birdbaths, roof gutters, and old tires dumped in vacant lots. Some species can breed in puddles left after a rainstorm. If you want to keep mosquitoes under control around your home, you need to be vigilant about dumping any standing water every few days. Most Mosquitoes Can Travel Only 2–3 Miles Your mosquitoes are basically your (and your neighbors) problem. Some varieties, like the Asian tiger mosquito, can fly only about 100 yards. Mosquitoes Detect CO2 75 Feet Away Carbon dioxide, which humans and other animals produce, is the key signal to mosquitoes that a potential blood meal is near. Theyve developed a keen sensitivity to CO2 in the air. Once a female senses CO2 in the vicinity, she flies back and forth through the CO2 plume until she locates her victim. Bug Zappers Don't Attract Mosquitoes Bug zappers give off light that attracts gnats, beetles, moths, and the like, but because mosquitoes are attracted to you by CO2, they are not effective at killing mosquitoes. They likely kill more beneficial insects and those eaten by songbirds than mosquitoes. They even take out parasitic wasps, which control other species. How Do You Kill Mosquitoes? Fogger machines that attract mosquitoes with CO2 and then trap them do work, but repellants for your yard and self may be the easiest and most cost-effective way to go. Why Do Mosquitoes Exist? Basically, mosquitoes exist because theyre next to impossible to wipe out. Species dont exist in a vacuum; as long as they can find food and dont have environmental pressure against them, theyll continue. Mosquitoes are millions of years old as a species. In the ecosystem, they do serve as food for other species (birds, frogs, and fish) and as pollinators. The larvae eat detritus in the water, helping to clean it. There are more than 3,000 species of mosquitoes, but only about 200 bite humans. Not Everyone Is Allergic to Mosquito Saliva Mosquito saliva, which lubricates the proboscis to glide into the skin, is responsible for the itching and bump on your skin, but not everyone is allergic to mosquito saliva. Some people even avoid getting bitten, and their sweat is being studied to develop repellents. Mosquitoes Have Benefitted Science The design of their proboscis has inspired scientists to design less-painful hypodermic needles, examine strategies to make needle insertion easier, and create insertion guides to better place tiny electrodes into the brain.

Managing strategy Essay Example | Topics and Well Written Essays - 3000 words

Managing strategy - Essay Example The second part of the report focuses on internal analysis of Netflix with VRIN framework adopted for conducting an analysis of company resources and capabilities. Based on the identified in the external and internal analysis, part three feature issues and challenges facing Netflix as it strives to remain competitive in the industry. Part four of the report analyses strategic options that will facilitate continued growth and development of Netflix with the ANSOFF Matrix being the analytical tool for identifying the options. Part five of the report evaluates the identified strategic growth options while part six focuses on the selected growth option before lastly making a brief conclusion and recommendation. Netflix operates in video renting and streaming industry with the company offering channels foe distribution of DVD rental by mail order, internet streaming of content through home devices such as PCs and internet TV. The company uses subscription-based services to customers who pay a monthly fee for both DVD rental and streaming services. The company had initially linked the two services, but has separated them in recent years meaning subscribers will no longer have access to both unlimited DVDs and unlimited online streaming in one subscription plan (Thompson, 2013). There are a number of political, economic, social, technological, legal and environmental factors with considerable impact on the operations of Netflix. Political and legal factors in the external market relates to laws and regulations regarding access and distribution of content by Netflix and and other vendors in existing in the industry. There is an increased concern about piracy with companies seeking to enhance their control regarding copyrights, patents, licensing and trademarks. While it is difficult for authorities to eradicate, piracy has a negative impact on revenues collected by vendors as it makes content

Plasma International and Blood Plasma Transfusions Case Study

Plasma International and Blood Plasma Transfusions - Case Study Example Blood most especially the one provided through donations by third world countries at a low price should not be sold back to them at exorbitant prices. Blood should be available to anyone at any time without charge or obligation because donors don’t gain preference over non-donors. I don’t agree with the writer because human blood, just like any other human body part should come at a price. People pay to replace their kidneys, arms, eyes knees even heart valves. Just like blood other body parts are as important so I don’t see why when it comes to the donation of blood it should be different. Just because blood comes from human who can continuously produce more, doesn’t mean one can collect it freely(Zimmer.Preston n.d) There are many things involved before, during and after someone is transfused with blood that is costly. Starting with purchasing needles, collection bags, sterilizers, vacuum containers, equipment for laboratory testing to verify the purity of the blood. Medical practitioners, as well as the supplies they use like lab coats, latex gloves, and protective equipment, need to be purchased. Also, transportation cost from the donor to the recipient should not be left out. According to me, it’s not unethical if the company k eeps the price to receive donor blood affordable to the recipient. And as long as it operates legally, it’s fine with me. After all, medicine nowadays is profit generating as any other. The existence of blood market does not threaten the right to donate freely (Zimmer.Preston (n.d) There are facts that contradict my argument, the fact that marketing threatens all rights to receive freely donated blood. The commercialization of blood discourages voluntary blood donors; someone will be reluctant to donate freely knowing very well that someone will be financially profitable out of it (Paying donors and the ethics of blood supply. n.d.).  Still, it seems likely that  when suppliers get paid, the would-be non-cash donor losses the sense that their contribution is necessary (Güceri, Fridman   & North Atlantic Treaty Organization, 2008).