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Rac is allways greater than Rdc due to skin effect which in
diactes less the freq less will be inductance and the
current will pass throug the entire cross sec area of
conductor.
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What is the level of measurement for allergies?
Skin prick tests are measured in millimeters (mm). Blood test check levels of Immunoglobulin E.
What are the chances of a light skinned woman and a dark skinned man to have a light skinned baby?
its about 50/50, but mostly depending on the skin to of the grand parents
How statistics can be misused?
There are too many ways to list, really, but here are a few common ones. First, and probably most common, is to assume that a statistical relationship equals a cause and effect one. You can, for example, quite accurately predict the damage a fire will do by counting the number of firefighters who show up to put it out. But that does not mean that firefighters cause fire damage. Other examples of this abuse can be seen everywhere in advertising. Just because kids who eat a healthy breakfast do better in school, that does not mean that the breakfast caused it or that if you suddenly start eating better your grades will improve. More likely, parents who have the sense and caring to prepare a healthy breakfast caused the kids to do better in school. Second, you can ignore other contributing variables. The classic example here is the fact that predominantly non-white neighborhoods have higher crime rates. For years, this statistic was touted as proof that non-whites are inherently violent and criminal-minded. Yet when you also consider the economics of a neighborhood, it turns out that poverty leads to higher crime, not skin color. Lastly, and this one is thankfully rare but also the most devious, you can intentionally delete cases or otherwise manipulate data to achieve the results you want. (Despite claims to the contrary, this rarely happens in legitimate science). But in general, a misuse of statistics has occurred any time that you rely too heavily on the numbers and forget that they are just numbers. If there is no practical connection between the numbers and what they represent, no common sense analysis of what the numbers mean and what could have been missed, then statistics is nothing more than just fancy math and fodder for sound bites on the evening news.
Reticulocyte count?
DefinitionA reticulocyte count measures the percentage of reticulocytes (slightly immature red blood cells) in the blood.How the test is performedBlood is typically drawn from a vein, usually from the inside of the elbow or the back of the hand. The site is cleaned with germ-killing medicine (antiseptic). The health care provider wraps an elastic band around the upper arm to apply pressure to the area and make the vein swell with blood.Next, the health care provider gently inserts a needle into the vein. The blood collects into an airtight vial or tube attached to the needle. The elastic band is removed from your arm.Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding.In infants or young children, a sharp tool called a lancet may be used to puncture the skin and make it bleed. The blood collects into a small glass tube called a pipette, or onto a slide or test strip. A bandage may be placed over the area if there is any bleeding.The blood sample is sent to a laboratory. A special stain is used to identify the reticulocytes.How to prepare for the testNo special preparation is necessary.How the test will feelWhen the needle is inserted to draw blood, some people feel moderate pain, while others feel only a prick or stinging sensation. Afterward, there may be some throbbing.Why the test is performedThe test is done to determine if red blood cells are being created in the bone marrow at an appropriate rate. The number of reticulocytes in the blood is a sign of how quickly they are being produced and released by the bone marrow.Normal ValuesThe normal range depends on the level of hemoglobin, and the range is higher if there is low hemoglobin due to bleeding or red cell destruction.What abnormal results meanA higher-than-normal percentage of reticulocytes may indicate:BleedingErythroblastosis fetalisHemolytic anemiaKidney diseasewith increased erythropoietinproductionA lower-than-normal percentage of reticulocytes may indicate:Bone marrow failure (for example, from drug toxicity, tumor, or infection)Cirrhosis of the liverFolate deficiencyIron deficiencyKidney disease with decreased erythropoietin productionRadiation therapyVitamin B-12deficiencyAdditional conditions under which the test may be performed:Anemia of chronic diseaseCongenital spherocytic anemiaDrug-induced immune hemolytic anemiaHemolytic anemia due to G6PD deficiencyIdiopathic aplastic anemiaIdiopathic autoimmune hemolytic anemiaImmune hemolytic anemiaPernicious anemiaSecondary aplastic anemiaWhat the risks areThere is very little risk involved with having your blood taken. Veins and arteries vary in size from one patient to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others.Other risks associated with having blood drawn are slight but may include:Excessive bleedingFainting or feeling light-headedHematoma (blood accumulating under the skin)Infection (a slight risk any time the skin is broken)Special considerationsThe reticulocyte count may be increased during pregnancy.ReferencesZuckerman K. Approach to the anemias. In: Goldman L, Ausiello D, eds. Cecil Medicine. 23rd ed. Philadelphia, Pa: Saunders Elsevier; 2007:chap 162.
Platelet count?
DefinitionA platelet count is a test to measure how many platelets you have in your blood. Platelets help the blood clot. They are smaller than red or white blood cells.Alternative NamesThrombocyte countHow the test is performedBlood is typically drawn from a vein, usually from the inside of the elbow or the back of the hand. The site is cleaned with germ-killing medicine (antiseptic). The health care provider wraps an elastic band around the upper arm to apply pressure to the area and make the vein swell with blood.Next, the health care provider gently inserts a needle into the vein. The blood collects into an airtight vial or tube attached to the needle. The elastic band is removed from your arm.Once the blood has been collected, the needle is removed, and the puncture site is covered to stop any bleeding.In infants or young children, a sharp tool called a lancet may be used to puncture the skin and make it bleed. The blood collects into a small glass tube called a pipette, or onto a slide or test strip. A bandage may be placed over the area if there is any bleeding.How to prepare for the testNo preparation is necessary. Tell your doctor if you are taking any medications, including over-the-counter medicines and supplements.Drugs that can lower platelet counts include chemotherapy drugs, chloramphenicol, colchicine, GP IIb/IIIa receptor antagonists, H2 blocking agents, heparin, hydralazine, indomethacin, isoniazid, quinidine, streptomycin, sulfonamides, thiazide diuretic, and tolbutamide.How the test will feelWhen the needle is inserted to draw blood, some people feel moderate pain, while others feel only a prick or stinging sensation. Afterward, there may be some throbbing.Why the test is performedThe number of platelets in your blood can be affected by many diseases. Platelets may be counted to monitor or diagnose diseases, or identify the cause of excess bleeding.Normal Values150,000 - 400,000 platelets per microliter (mcL).Note: Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.The examples above show the common measurements for results for these tests. Some laboratories use different measurements or may test different specimens.What abnormal results meanA lower-than-normal number of platelets (thrombocytopenia) may be due to:Cancer chemotherapyCertain medicationsDisseminated intravascular coagulation (DIC)Hemolytic anemiaHypersplenismIdiopathic thrombocytopenic purpura (ITP)LeukemiaMassive blood transfusionProsthetic heart valveThombotic thrombocytopenic purpura (TTP)Celiac diseaseVitamin K deficiencyA higher-than-normal number of platelets (thrombocytosis) may be due to:AnemiaChronic myelogenous leukemia (CML)Polycythemia veraPrimary thrombocythemiaRecent spleen removalWhat the risks areThere is very little risk involved with having your blood taken. Veins and arteries vary in size from one patient to another and from one side of the body to the other. Taking blood from some people may be more difficult than from others.Other risks associated with having blood drawn are slight but may include:Excessive bleedingFainting or feeling light-headedHematoma (blood accumulating under the skin)Infection (a slight risk any time the skin is broken)ReferencesSchmaier AH. Laboratory evaluation of hemostatic and thrombotic disorders. In: Hoffman R, Benz EJ Jr, Shattil SJ, et al, eds. Hoffman Hematology: Basic Principles and Practice. 5th ed. Philadelphia, Pa: Churchill Livingstone Elsevier; 2008:chap 122.Reviewed ByReview Date: 08/31/2011A.D.A.M. Editorial Team: David Zieve, MD, MHA, and David R. Eltz. Previously reviewed by David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine (2/13/2011).
The decrease in effective conductor cross section at high frequencies?
Is called skin effect. The higher the frequency, the worse the issue.
Does rubber conduct electricity at very high frequencies?
Rubber doesn't conduct electricity well at any frequency. But to the extent that it does conduct, it's better at low frequencies than high, because of the skin effect.
Why is speaker wire stranded not solid?
high frequencies utilize the skin effect, running on the exterior of the conductor, with low frequencies utilizing the core of the conductor. Stranded wire has more skin area and would enhance higher frequencies, while solid wire would enhance lower frequencies. stranded is more flexible
What is meant by skin effect?
The skin effect occurs in conductors carrying alternating currents, where the tendency is for the current to flow towards the surface of the conductor. The effect increases with frequency. At radio frequencies, the skin effect is so pronounced, that there is little point in using solid conductors, so tubes are used instead.The skin effect is responsible for the so-called 'AC resistance'. This is because the skin effect acts to reduce the effective cross-sectional area of a conductor, thus increasing its resistance compared to when a DC current passes through the conductor.
Why does the skin effect in radio frequency caused?
Skin effect is the tendency of an alternating electric current (AC) to distribute itself within a conductor so that the current density near the surface of the conductor is greater than that at its core. That is, the electric current tends to flow at the "skin" of the conductor, at an average depth called the skin depth. The skin effect causes the effective resistance of the conductor to increase with the frequency of the current because much of the conductor does little. Skin effect is due to eddy currents set up by the AC current. At 60 Hz in copper, skin depth is about a centimetre. At high frequencies skin depth is much smaller.
Why twisted conductors instead of solid are used?
I suppose you mean cables, made out of many threads. Those are easier to bend, and thus to install. Also, it may help reduce the skin effect - this is especially relevant at high frequencies.
What reaction occurs when rubbing alcohol is placed on the arm?
The cooling effect of alcohol on the skin is the result of?
The cooling effect of perspiration as it evaporates from the skin is the result of high of water?
Enthalpy of vaporization
What is the reason ofskin effect?
Skin effect is the behavior of electron current flow to mostly be on the surface, or "skin", of the conductor. This is due to the fact that like charges repel one another, so the electrons migrate away from each other to the skin of the conductor. This effect is particularly noticable with high voltage circuits. The impact of skin effect is that the inner parts of the conductor are not really participating in supporting the current flow, so the conductor must be made larger than expected in order to carry the current flow. In fact, many high voltage transmission conductors have a light weight non-conductive core that is used for tensile strength rather than for current carrying capacity. Skin effect is also related to the system frequency. At higher and higher frequencies, electrons tend to migrate even more to the outer surface of the conductor. In low frequency systems it is not so much a factor because it is negligible, unless high voltage such as in long distance power transmission systems in involved
Can leprosy effect your skin?
yes. leprosy does effect your skin
What drugs skin side effect?
WHAT drugs effect our skin? It make our skin rough.
What is skin effect of AC current?
The higher the frequency of the current is, the further the travelling electrons are from the center of the conductor section. That's skin effect. In very high frenquencies, such an effect even increases the resistance of the conductor because the current has less place to travel in.
