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| {{other uses|Reactance (disambiguation)}}
| | Psoriasis in severe cases has been observed to affect health-related quality of life that is similar to the effect of other chronic diseases. Exercise is actually proven to increase energy levels and also help reduce anxiety. People often need to try out different treatments before they find one that works for them. Lots of physicians think that in some cases the true reason for psoriasis is the lack of an appropriate diet program. The doctors will say there is no cure for psoriasis. <br><br>Even if you are experiencing peeling skin or any of type of psoriasis while taking proteins, vitamins A, vitamins B and vitamins C, it is possible that you can get relief. Examples of environmental influences include climate, trauma to the skin, or an infection of the ear or upper respiratory tract. Folliculitis of the scalp is a superficial bacterial scalp infection of the hair follicles. You should avoid all commercial versions of herbal skin care products, because their products are not really natural herbs but instead are artificial scents with little bit of essential oils. Most agree that those with exceptionally high IQs are much more likely to be afflicted with psoriasis. <br><br>Using moisturizers on a regular basis also helps to curtail Psoriasis. If you do not like to waste money on the costly recommended medicines or drugs that's not give a best results. All of this prompted Katy to "roll up her sleeves" and get to work. Some of the products of Deep Sea Cosmetics are ideally used when bathing and this helps in releasing toxins or free radicals. As far as soaps are concerned, cleansers are suggested that are liquid based and don't have a tendency to lather as much as a standard bar soap does. <br><br>The greatest thing is that Katy found a treatment for her psoriasis, and she shared this program with others to have them try it before she introduced this program. Humidifiers increase moisture level of surrounding air and prevent drying of skin. The individual in the chair next to you at work could have to deal with psoriasis and also you would definitely certainly never realize. All these antioxidants lessen the damage done by the sun and prevent skin cancer. is also used in more than 100 cosmetic formulations that appear in a wide range of products, including hair tonics, anti-dandruff products, and perfumes. <br><br>As apparent via numerous existing studies, stress can trigger start of skin psoriasis, hence meditation and relaxation treatments can also be regarded as as alternative system for dealing with psoriatic patients. This can aid in reducing anxiety and can lift a person. About 50% of patients who are suffering from psoriasis are because of hereditary factors. Recent years have also seen psoriasis being referred to as a form of leprosy. As was discussed at the start of this article, educated decisions concerning your skin care are usually the very best ones.<br><br>If you adored this article and you would like to get additional details regarding psoriasis remedies, [http://www.dominionradio.info/ visit the next web site], kindly check out the web-page. |
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| In electrical and electronic systems, '''reactance''' is the opposition of a circuit element to a change of [[electric current]] or [[voltage]], due to that element's [[inductance]] or [[capacitance]]. A built-up [[electric field]] resists the change of voltage on the element, while a [[magnetic field]] resists the change of current. The notion of reactance is similar to [[electrical resistance]], but they differ in several respects.
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| An ideal [[resistor]] has zero reactance, while ideal [[inductor]]s and [[capacitor]]s consist entirely of reactance. The magnitude of the reactance of an inductor is proportional to frequency, while the magnitude of the reactance of a capacitor is inversely proportional to frequency.
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| == Analysis ==
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| In [[phasor]] analysis, reactance is used to compute amplitude and phase changes of [[Sine wave|sinusoidal]] [[alternating current]] going through the circuit element. It is denoted by the symbol <math>\scriptstyle{X}</math>.
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| Both reactance <math>\scriptstyle{X}</math> and [[Electrical resistance|resistance]] <math>\scriptstyle{R}</math> are components of [[Electrical impedance|impedance]] <math>\scriptstyle{Z}</math>.
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| :<math>Z = R + jX\,</math>
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| :where
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| *<math>\scriptstyle{Z}</math> is the [[Electrical impedance|impedance]], measured in ohms.
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| *<math>\scriptstyle{R}</math> is the [[Electrical resistance|resistance]], measured in ohms.
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| *<math>\scriptstyle{X}</math> is the reactance, measured in ohms.
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| *<math>\scriptstyle j \;=\; \sqrt{-1}</math>
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| Both capacitive reactance <math>\scriptstyle{X_C}</math> and inductive reactance <math>\scriptstyle{X_L}</math> contribute to the total reactance <math>\scriptstyle{X}</math>.
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| :<math>{X = X_L - X_C = \omega L -\frac {1} {\omega C}}</math>
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| :where
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| * <math>\scriptstyle{X_C}</math> is the [[Capacitance|capacitive]] reactance, measured in ohms
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| * <math>\scriptstyle{X_L}</math> is the [[Inductance|inductive]] reactance, measured in ohms
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| Although <math>\scriptstyle{X_L}</math> and <math>\scriptstyle{X_C}</math> are both positive by convention, the capacitive reactance <math>\scriptstyle{X_C}</math> makes a negative contribution to total reactance.
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| Hence,
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| * If <math>\scriptstyle X \;>\; 0</math>, the reactance is said to be [[Inductance|inductive]].
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| * If <math>\scriptstyle X \;=\; 0</math>, then the impedance is purely [[Electrical resistance|resistive]].
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| * If <math>\scriptstyle X \;<\; 0</math>, the reactance is said to be [[Capacitance|capacitive]]
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| == Capacitive reactance ==
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| {{main|Capacitance}}
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| '''Capacitive reactance''' is an opposition to the change of voltage across an element. Capacitive reactance <math>\scriptstyle{X_C}</math> is [[inversely proportional]] to the signal [[frequency]] <math>\scriptstyle{f}</math> (or [[angular frequency]] ω) and the [[capacitance]] <math>\scriptstyle{C}</math>.<ref>Irwin, D. (2002). ''Basic Engineering Circuit Analysis'', page 274. New York: John Wiley & Sons, Inc.</ref>
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| :<math>X_C = \frac {1} {\omega C} = \frac {1} {2\pi f C}</math> <ref>http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html</ref>
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| A capacitor consists of two [[Electrical conduction|conductor]]s separated by an [[Electrical insulation|insulator]], also known as a [[dielectric]].
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| At low frequencies a capacitor is [[open circuit]], as no [[Electric current|current]] flows in the dielectric. A [[Direct current|DC]] voltage applied across a capacitor causes positive [[Electrical charge|charge]] to accumulate on one side and negative [[Electrical charge|charge]] to accumulate on the other side; the [[electric field]] due to the accumulated charge is the source of the opposition to the current. When the [[potential]] associated with the charge exactly balances the applied voltage, the current goes to zero.
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| Driven by an AC supply, a capacitor will only accumulate a limited amount of charge before the potential difference changes polarity and the charge dissipates. The higher the frequency, the less charge will accumulate and the smaller the opposition to the current.
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| == Inductive reactance ==
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| {{main|Inductance}}
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| '''Inductive reactance''' is an opposition to the change of current through an element. Inductive reactance <math>\scriptstyle{X_L}</math> is [[Proportionality (mathematics)|proportional]] to the sinusoidal signal [[frequency]] <math>\scriptstyle{f}</math> and the [[inductance]] <math>\scriptstyle{L}</math>. | |
| :<math>X_L = \omega L = 2\pi f L</math>
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| The average current flowing in an [[inductance]] <math>\scriptstyle{L}</math> in series with a sinusoidal AC voltage source of RMS [[amplitude]] <math>\scriptstyle{A}</math> and frequency <math>\scriptstyle{f}</math> is equal to: | |
| :<math>I_L = {A \over \omega L} = {A \over 2\pi f L}.</math>
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| The average current flowing in an [[inductance]] <math>\scriptstyle{L}</math> in series with a square wave AC voltage source of RMS [[amplitude]] <math>\scriptstyle{A}</math> and frequency <math>\scriptstyle{f}</math> is equal to:
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| :<math>I_L = {A \pi^2 \over 8 \omega L} = {A\pi \over 16 f L}</math> making it appear as if the inductive reactance to a square wave was <math>X_L = {16 \over \pi} f L</math>
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| An inductor consists of a [[Coil#Electromagnetic coils|coiled conductor]]. [[Faraday's law of induction|Faraday's law]] of electromagnetic induction gives the counter-[[Electromotive force|emf]] <math>\scriptstyle{\mathcal{E}}</math> (voltage opposing current) due to a rate-of-change of [[magnetic flux density]] <math>\scriptstyle{B}</math> through a current loop.
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| :<math>\mathcal{E} = -{{d\Phi_B} \over dt}</math>
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| For an inductor consisting of a coil with <math>\scriptstyle N</math> loops this gives.
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| :<math>\mathcal{E} = -N{d\Phi_B \over dt}</math>
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| The counter-emf is the source of the opposition to current flow. A constant [[direct current]] has a zero rate-of-change, and sees an inductor as a [[short-circuit]] (it is typically made from a material with a low [[resistivity]]). An [[alternating current]] has a time-averaged rate-of-change that is proportional to frequency, this causes the increase in inductive reactance with frequency.
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| == Phase relationship ==
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| The phase of the voltage across a purely reactive device (a capacitor with an infinite resistance or an inductor with a resistance of zero) ''lags'' the current by <math>\scriptstyle{\pi/2}</math> radians for a capacitive reactance and ''leads'' the current by <math>\scriptstyle{\pi/2}</math> radians for an inductive reactance. Note that without knowledge of both the resistance and reactance the relationship between voltage and current cannot be determined.
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| The origin of the different signs for capacitive and inductive reactance is the phase factor in the impedance.
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| :<math>\begin{align}
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| \tilde{Z}_C &= {1 \over \omega C}e^{j(-{\pi \over 2})} = -j\left({ \frac{1}{\omega C}}\right) = -jX_C \\
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| \tilde{Z}_L &= \omega Le^{j{\pi \over 2}} = j\omega L = jX_L\quad
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| \end{align}</math>
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| For a reactive component the sinusoidal voltage across the component is in quadrature (a <math>\scriptstyle{\pi/2}</math> phase difference) with the sinusoidal current through the component. The component alternately absorbs energy from the circuit and then returns energy to the circuit, thus a pure reactance does not dissipate power.
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| ==See also==
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| *[[Electrical measurements]]
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| * [[Susceptance]]
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| * [[Magnetic reactance]]
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| == References ==
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| # Pohl R. W. ''Elektrizitätslehre.'' – Berlin-Göttingen-Heidelberg: Springer-Verlag, 1960.
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| # Popov V. P. ''The Principles of Theory of Circuits.'' – M.: Higher School, 1985, 496 p. (In Russian).
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| # [[Karl Küpfmüller|Küpfmüller K.]] ''Einführung in die theoretische Elektrotechnik,'' Springer-Verlag, 1959.
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| # {{cite book | author = Young, Hugh D. | coauthors = Roger A. Freedman and A. Lewis Ford | title = Sears and Zemansky's University Physics | origyear = 1949 | year = 2004 | edition = 11 ed | accessdate = 2006-09-30 | publisher = [[Addison Wesley]] | location = [[San Francisco]] | isbn= 0-8053-9179-7}}
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| <references/>
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| == External links ==
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| * [http://www.magnet.fsu.edu/education/tutorials/java/inductivereactance/index.html Interactive Java Tutorial on Inductive Reactance] National High Magnetic Field Laboratory
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| [[Category:Electronics]]
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| [[Category:Physical quantities]]
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| [[he:עכבה חשמלית#היגב]]
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Psoriasis in severe cases has been observed to affect health-related quality of life that is similar to the effect of other chronic diseases. Exercise is actually proven to increase energy levels and also help reduce anxiety. People often need to try out different treatments before they find one that works for them. Lots of physicians think that in some cases the true reason for psoriasis is the lack of an appropriate diet program. The doctors will say there is no cure for psoriasis.
Even if you are experiencing peeling skin or any of type of psoriasis while taking proteins, vitamins A, vitamins B and vitamins C, it is possible that you can get relief. Examples of environmental influences include climate, trauma to the skin, or an infection of the ear or upper respiratory tract. Folliculitis of the scalp is a superficial bacterial scalp infection of the hair follicles. You should avoid all commercial versions of herbal skin care products, because their products are not really natural herbs but instead are artificial scents with little bit of essential oils. Most agree that those with exceptionally high IQs are much more likely to be afflicted with psoriasis.
Using moisturizers on a regular basis also helps to curtail Psoriasis. If you do not like to waste money on the costly recommended medicines or drugs that's not give a best results. All of this prompted Katy to "roll up her sleeves" and get to work. Some of the products of Deep Sea Cosmetics are ideally used when bathing and this helps in releasing toxins or free radicals. As far as soaps are concerned, cleansers are suggested that are liquid based and don't have a tendency to lather as much as a standard bar soap does.
The greatest thing is that Katy found a treatment for her psoriasis, and she shared this program with others to have them try it before she introduced this program. Humidifiers increase moisture level of surrounding air and prevent drying of skin. The individual in the chair next to you at work could have to deal with psoriasis and also you would definitely certainly never realize. All these antioxidants lessen the damage done by the sun and prevent skin cancer. is also used in more than 100 cosmetic formulations that appear in a wide range of products, including hair tonics, anti-dandruff products, and perfumes.
As apparent via numerous existing studies, stress can trigger start of skin psoriasis, hence meditation and relaxation treatments can also be regarded as as alternative system for dealing with psoriatic patients. This can aid in reducing anxiety and can lift a person. About 50% of patients who are suffering from psoriasis are because of hereditary factors. Recent years have also seen psoriasis being referred to as a form of leprosy. As was discussed at the start of this article, educated decisions concerning your skin care are usually the very best ones.
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