what is the physics of the stethoscope?
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Stethoscope \nDefinition \nThe stethoscope is an instrument used for auscultation, or listening to sounds produced by the body. It is used primarily to listen to the lungs, heart, and intestinal tract. It is also used to listen to blood flow in peripheral vessels and the heart sounds of developing fetuses in pregnant women.\n\n\n\nPurpose \nA stethoscope is used to detect and study heart, lung, stomach, and other sounds in adult humans, human fetuses, and animals. Using a stethoscope, the listener can hear normal and abnormal respiratory, cardiac, pleural, arterial, venous, uterine, fetal and intestinal sounds.\n\n\n\nDemographics \nAll health care providers and students learn to use a stethoscope.\n\n\n\nDescription \nStethoscopes vary in their design and material. Most are made of Y-shaped rubber tubing. This shape allows sounds to enter the device at one end, travel up the tubes and through to the ear pieces. Many stethoscopes have a two-sided sound-detecting device or head that listeners can reverse, depending on whether they need to hear high or low frequencies. Some newer models have only one pressure-sensitive head. The various types of instruments include: binaural stethoscopes, designed for use with both ears; single stethoscopes, designed for use with one ear; differential stethoscopes, which allow listeners to compare sounds at two different body sites; and electronic stethoscopes, which electronically amplify tones. Some stethoscopes are designed specifically for hearing sounds in the esophagus or fetal heartbeats.\n\n\n\nDiagnosis/Preparation \nTraining\n\nStethoscope users must learn to assess what they hear. When listening to the heart, one must listen to the left side of the chest, where the heart is located. Specifically, the heart lies between the fourth and sixth ribs, almost directly below the breast. The stethoscope must be moved around. A health care provider should listen for different sounds coming from different locations. The bell (one side of the head) of the instrument is generally used for listening to low-pitched sounds. The diaphragm (the other side of the head) of the instrument is used to listen to different areas of the heart. The sounds from each area will be different. "Lub-dub" is the sound produced by the normal heart as it beats. Every time this sound is detected, it means that the heart is contracting once. The noises are created when the heart valves click to close. When one hears "lub," the atrioventricular valves are closing. The "dub" sound is produced by the pulmonic and aortic valves. Other heart sounds, such as a quiet "whoosh," are produced by "murmurs." These sounds are produced when there are irregularities in the path of blood flow through the heart. The sounds reflect turbulence in normal blood flow. If a valve remains closed rather than opening completely, turbulence is created and a murmur is produced. Murmurs are not uncommon; many people have them and are unaffected. They are frequently too faint to be heard and remain undetected.\n\nThe lungs and airways require different listening skills from those used to detect heart sounds. The stethoscope must be placed over the chest, and the person being examined must breathe in and out deeply and slowly. Using the bell, the listener should note different sounds in various areas of the chest. Then, the diaphragm should be used in the same way. There will be no wheezes or crackles in normal lung sounds.\n\nCrackles or wheezes are abnormal lung sounds. When the lung rubs against the chest wall, it creates friction and a rubbing sound. When there is fluid in the lungs, crackles are heard. A high-pitched whistling sound called a wheeze is often heard when the airways are constricted.\n\nWhen the stethoscope is placed over the upper left portion of the abdomen, gurgling sounds produced by the stomach and small intestines can usually be heard just below the ribs. The large intestines in
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A  "heart  murmur"  is the general  name given to an unusual  heartbeat sound.  Not always, but usually,  the heart rhythm is normal, but there's some other little extra noise in there.   I am   rather curious that you say somebody in ER  asked YOU what  type it was, because anybody efficient in the use of a  stethoscope  is normally  able to identify  the type of sound and  match it  to the probable cause.   Other  tests, of course,  are  then done  for confirmation.\n                                                    Some years ago when a doctor  first identified a heart murmur in me,  he immediately  said "You seem to have a couple of heart valves not functioning  exactly  right    Did you by   chance  ever have   rheumatic  fever as  a child?"    I  told him  that I had.      Nowadays  doctors know  that   childhood  rheumatic  fever  has to be  treated  with  strong  antibiotics, because  the  organism  that  causes the fever, attacks  the heart  valves  -  usually the  aortic  and/or  mitral valves.    The patient  seems to  recover uneventfully,  but before they realised the need for antibiotics, some scarring occurred to the  attacked  valves, which, over a number of years,  thickens  the valve flaps and  prevents them from opening and shutting  completely.    The  backwash of blood  into the heart chamber,   as the heart  rests  following a  pump, creates  that  "schloooping"  sound  that  the doctor hears in his stethoscope.    That,  of course, is just one  example of a heart murmur.       There are other congenital murmurs which are  just the  peculiarity of that particular heart, and an example of that would be what's called  "floppy valve syndrome"  where instead of the valve cusps snapping open and shut in a  nice crisp  action,  that  particular valve kind  of "flubbers"  which  creates its own  pretty identifiable sound.    A doctor will always tell a  patient with a  confirmed "floppy  valve" that it's nothing  at all to  be concerned about,  and  my guess would have  been  that you could have one of those,  which would have been why  your doctor  told you not to worry.   BUT  you are  also mentioning   that your heart  "skips"  (which is also called  a murmur).     Since you haven't got  any history of other heart  trouble (you didn't mention any)  this,  too, may  just be a harmless minor "arrhythmia" (or unusual  rhythm).     However, all things considered,   what  I would do if I  were you, is   go see your regular primary care physician,   tell him the story of your recent visit to ER  with reference to the heart murmur, and then do NOT  leave his office until he has had  a good sit  down  visit  with you and fully  explained what he thinks this could be,  and  made arrangements for you to have further diagnostic testing and a consultation with a  cardiologist.    This may sound like  taking a sledgehammer to  squash a butterfly.    On the other hand,  I  assure you that the last words you ever want to hear  out of  a doctor's  mouth , somewhere down the road   is "If only you had had this investigated  sooner,  we could have dealt with it sooo much  easier.     By  the  way,  the diagnostic  tests   to confirm  the  exact nature of  your  murmur, are non-invasive, and don't hurt  a bit.    Good  luck.
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there is a great article on how stuff works .com, its quite long but gives a very nice description of everything and how it works\n\nhttp://electronics.howstuffworks.com/mri.htm
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look at this 3D pic then read\n\nhttp://library.thinkquest.org/C003758/rotate.htm\n\nIn the human body, the heart is normally situated slightly to the left of the middle of the thorax, underneath the sternum (breastbone). The heart is usually felt to be on the left side because the left heart (the left part of the heart) is stronger (it pumps the blood out). The heart is enclosed by a sac known as the pericardium and is surrounded by the lungs.Betwen the pericardium and the heart there is a serous fluid to reduce friction during heart contractions. The apex is the blunt point at the base of the heart. A stethoscope can be placed directly over the apex and count the beats. In normal adults, its mass is 250-350 g (8-11 oz), but extremely diseased hearts can be up to 1000 g (2 lb) in mass. It consists of four chambers, the two upper atria (singular: atrium ) and the two lower ventricles. On the right is a picture of a fresh human heart which was just removed from a 64 year old British gentleman. The mass for a thin white male is usually 270-300 grams (9-11 ounces) with little fat.\n\nA septum divides the right atrium and ventricle from the left atrium and ventricle, preventing blood from passing between them. Valves between the atria and ventricles (atrioventricular valves) maintain coordinated unidirectional flow of blood from the atria to the ventricles. The ventricular systole consists of the contraction of the ventricles and flow of blood into the circulatory system. Again, once all the blood empties from the ventricles, the pulmonary and aortic semilunar valves close. Finally complete cardiac diastole involves relaxation of the atria and ventricles in preparation for refilling with circulating blood.\n\nThe function of the right side of the heart (see right heart) is to collect deoxygenated blood from the body and pump it into the lungs (pulmonary circulation)so that carbon dioxide can be dropped off and oxygen picked up. This happens through a process called diffusion. The left side (see left heart) collects oxygenated blood from the lungs and pumps it out to the body (systemic circulation). On both sides, the lower ventricles are thicker than the upper atria.\nOxygen-depleted or deoxygenated blood from the body enters the right atrium through two great veins, the superior vena cava which drains the upper part of the body and the inferior vena cava that drains the lower part which drains the portal cyrculation too full with nutrients to nourish the body. The blood then passes through the tricuspid valve to the right ventricle. The right ventricle pumps the deoxygenated blood to the lungs, through the pulmonary artery. In the lungs gaseous exchange takes places and the blood releases carbon dioxide into the lung cavity and picks up oxygen which is called external respiration. The oxygenated blood then flows through pulmonary veins to the left atrium. From the left atrium this newly oxygenated blood passes through the mitral valve (also called the bicuspid valve) to enter the left ventricle. The left ventricle then pumps the blood through the aorta to the entire body. Even the lungs take some of the blood supply from the aorta via bronchial arteries.\n\nThe left ventricle is much more muscular, which is 1.3 - 1.5 cm (.5-.6 in) thick, than the right, 0.3 - 0.5 cm ( .1-.2 in) thick, as it has to pump blood around the entire body, which involves exerting a considerable force to overcome the vascular pressure. As the right ventricle needs to pump blood only to the lungs, it requires less muscle.\n\nEven though the ventricles lie below the atria, the two vessels through which the blood exits the heart (the pulmonary artery and the aorta) leave the heart at its top side.\n\nThe contractile nature of the heart is due to the presence of cardiac muscle in its wall which can work continuously without fatigue. The heart wall is made of three distinct layers. The first is the outer epicardium which is composed of a layer of flattened epi
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It is like SONAR.  A high frequency sound is emitted that bounces off surfaces inside your body.  The bounced back sound is collected and is used to generate a picture of your insides.
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the buoyancy of the object and its volume.
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I won't do your homework for you. But I will tell you this:\n\n\n1a&b. These should be common sense. Go outside and turn on the garden hose and tell your teacher what you've observed.\n2a. Look up BERNOULLI'S LAW as it pertains to fluid pressure through a tube. There is a formula that related pressure to hose diameter and volume.\nb. The answer is: high pressure is bad for vessels weakened by atherosclerosis.
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In physics it is acoustics.
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i  think it referer to a problem that doctors are having with some valves that help pump blood in patients hearts. look it up on the internet and you will find it im sure. then thus explain the device and how and when it is used and find out if the the device is agreeable for research to benifit other persons. and why the research is necessary. give that a  go and see if i got it. good luck 2 u mexxxi
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physics is present in every aspect of this universe...\nas a nurse u need to measure a lot of human activities like blood pressure,heart rate etc....these r measured with the help of different apparatus....the experiments that u perform now will give u a brief introduction of the different phenomenon that take place.\n   These experiments will further help u to understand the mesurement system n will also help u to find out correct measurements.......\n        keep enjoying the experiments...have fun... :)
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The top number is the systolic rate,the bottom number is the diastolic rate.\n\nSystolic pressure (the higher,first #) measures the force that the blood exerts on the artery walls as the heart contracts to pump the blood.\n\nDiastolic pressure (the lower second #) is the measurement of force as the heart relaxes to allow blood to flow to the heart.
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Airway, Breathing, Circulation
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nobody here has got it exactly right. \n\nhere's a link that will tell you everything you ever wanted to know about it (and more)  http://en.wikipedia.org/wiki/Liquid_breathing\n\nenjoy
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A sphygmomanometer (note spelling) works by completely cutting off the blood flow with high pressure, and then gradually decreasing that pressure until blood flows again.  The nurse determines this by listening with a stethoscope.  When she first hears blood begin to flow with a loud sound, that is the systolic blood pressure.  When the sound is no longer heard, that is the diastolic blood pressure.  So the cuff just reports how much pressure it is applying.  The nurse has to determine at what point the body responds.
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There is a very large book called "The Handbook of Chemestry and Physics"  This is a very good reference.\n\nAlso, at Barns & Noble there is a forumla sheet called Physics (SparkCharts).  Very helpful.\n\nFinally, look for the Physics for Dummies.  I have found that when tutoring and teaching, the explainations help me to better understand what is happening in terms that I can communicate.\n\nGood luck in your studies.
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Ha ha ha. The question is weird unless you are referring to something specific in physics. Otherwiss,\n\nLike Patient who lies down on bed, remains on bed because of gravity :)\nOr Simple stuff like - the stethoscope lets you hear the heart beat because of physical principals of sound movement.
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Dear Sir,\n\nPhysics governs the world as we know it. Seriously, you use it everyday, and you will need to know it to be successful in nursing. For example, there's a difference between someone who was hit with a car traveling 5 mph, versus one that travels 115 mph. That difference being breathing and circulation. \n\nNevertheless, there is a strong correlation (r=.9445) between nursing and physics. Here' s another example: let's say I yell at you in passing. You will hear the loudest volume and highest pitch of my yelling as I'm directly in front of you. This is relevant when your charge nurse begins to yell at you from a distance, versus when she/he yells at you from 6 inches away. \n\nHope this helps,\n\nPianoguy