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| | If you were younger, perhaps we were 1 of those lucky persons who didnt need weight reduction help. Maybe we were chasing kids, working at an outside job, cooking, cleaning plus living an active lifestyle. Its not which guys over 50 plus post-menopausal females are not active. However usually they are less active. This will be due to physical limitations, like arthritis, or considering they have merely gotten employed to a more sedentary life-style in retirement or if they are nonetheless working.<br><br>What weight would I be pleased with when my ideal is too low? This really is a weight that's not the ideal, but it would satisfy us; be within a healthy weight range plus will be more reasonable given the present lifestyle. I like to compare my clients' goals to the [http://safedietplansforwomen.com/bmi-chart bmi chart] for the healthiest weight ranges for their height. Here's one more path to take green, BMI green, that is (The bmi chart is colored coded with green because the healthy weight ranges. Take a guess the color for unhealthiest?) Scroll down for a link to a bmi chart where I give all of the hyperlinks.<br><br>A BMI calculator shows whether you're underweight, regular, obese, or overweight. Keep in your mind, though, it is a rough estimate of the ratio of the weight and height. Although the BMI is considered a body fat calculator, sometimes people that are muscular are not able to correctly gauge their body fat. Why behind this really is that muscle weight is heavier than fat. So, they might weigh more for their height, yet it really is muscle weight plus not fat at all. However, for those that are barely active, the BMI calculator is a remarkable tool in gauging their body fat.<br><br>Lets say an adult male is 60 and weighs 200 pounds. According to this chart, his BMI would be 27.1, which puts him into the overweight category. If he loses 17 pounds, the same man, today at 183 pounds, would have a BMI of 24.8, which would put him in the general weight category.<br><br>Having sex using the missionary position assist to get pregnant- the time-proven 'man-on-top' position works with gravity to encourage semen flow toward the uterus to maximize the chance of the sperm uniting with the egg plus causing conception. One of the associated right tips on getting pregnant is -- following ejaculation, the female could stay on her back with her legs bent a few minutes to further maximize semen flow toward the uterus.<br><br>With my plan, you'll eat three food bmi chart women plus three snacks a day. Each individual will have a different number of calories which he or she could eat per day and nonetheless lose at least 1 pound per week (and more with exercise). You start with acquiring the BMI.<br><br>That is not to state which the changes in preference were big, with the age of the woman models rarely being above 25 years. Same used to the alternative measurements. During the 40 years in question the lowest Body Mass Index was 16 plus highest was 20, with the average being about middle in between (to calculate BMI visit this BMI Calculator). Same applied to Waist-to-Hip ratio which stayed in the range of .57 to .73.<br><br>There are too little fluctuations in the BMI thresholds for the both sexes, plus for different races. For instance, health practice suggests which the grade of normal body mass chart should be lower for people of oriental origin. If you've any worries or concerns about a Body Mass Index then see the doctor. |
| [[Image:Series circuit.svg|right|thumb|A series circuit with a [[voltage source]] (such as a battery) and 3 resistors]]
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| Components of an [[Electrical network|electrical circuit]] or [[electronic circuit]] can be connected in [[topology (electronics)|many different ways]]. The two simplest of these are called '''series''' and '''parallel''' and occur very frequently. Components connected in series are connected along a single path, so the same [[electric current|current]] flows through all of the components.<ref name=R&H321>Resnick ''et al.'' (1966), Chapter 32, Example 1.</ref><ref>Smith, R.J. (1966), page 21</ref> Components connected in parallel are connected so the same [[voltage]] is applied to each component.<ref name=R&H324>Resnick ''et al.'' (1966), Chapter 32, Example 4.</ref>
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| A circuit composed solely of components connected in series is known as a '''series circuit'''; likewise, one connected completely in parallel is known as a '''parallel circuit'''.
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| In a series circuit, the current through each of the components is the same, and the [[voltage]] across the circuit is the sum of the voltages across each component.<ref name=R&H321/> In a parallel circuit, the voltage across each of the components is the same, and the total current is the sum of the currents through each component.<ref name=R&H324/>
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| As an example, consider a very simple circuit consisting of four light bulbs and one 6 V [[battery (electricity)|battery]]. If a wire joins the battery to one bulb, to the next bulb, to the next bulb, to the next bulb, then back to the battery, in one continuous loop, the bulbs are said to be in series. If each bulb is wired to the battery in a separate loop, the bulbs are said to be in parallel. If the four light bulbs are connected in series, there is same current through all of them, and the [[voltage drop]] is 1.5 V across each bulb, which may not be sufficient to make them glow. If the light bulbs are connected in parallel, the currents through the light bulbs combine to form the current in the battery, while the voltage drop is 6.0 V across each bulb and they all glow.
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| In a series circuit, every device must function for the circuit to be complete. One bulb burning out in a series circuit breaks the circuit. In parallel circuits, each light has its own circuit, so all but one light could be burned out, and the last one will still function.
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| == Series circuits ==<!-- This section is linked from [[Battery (electricity)]] -->
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| '''Series circuits''' are sometimes called ''current''-coupled or [[Daisy chain (electrical engineering)|daisy chain]]-coupled. The [[Electric current|current]] in a series circuit goes through every component in the circuit. Therefore, all of the components in a series connection carry the same current. There is only one path in a series circuit in which the current can flow. | |
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| A series circuit's main disadvantage or advantage, depending on its intended role in a product's overall design, is that because there is only one path in which its current can flow, opening or breaking a series circuit at any point [[Single point of failure|causes the entire circuit to "open" or stop operating]]. For example, if even one of the light bulbs in an older-style string of [[Christmas tree lights]] burns out or is removed, the entire string becomes inoperable until the bulb is replaced.
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| {{anchor|Iseries}}
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| === Current ===
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| :<math>
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| I = I_1 = I_2 = \dots = I_n
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| </math>
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| In a series circuit the current is the same for all elements.
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| {{anchor|Rseries}}
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| === Resistors ===
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| The total resistance of resistors in series is equal to the sum of their individual resistances: | |
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| [[Image:Resistors in series.svg|This is a diagram of several resistors, connected end to end, with the same amount of current through each.]]
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| :<math>R_\mathrm{total} = R_1 + R_2 + \cdots + R_n</math>
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| {{anchor|Lseries}}
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| [[Electrical conductance]] presents a reciprocal quantity to resistance. Total conductance of a series circuits of pure resistors, therefore, can be calculated from the following expression:
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| :<math>\frac{1}{G_\mathrm{total}} = \frac{1}{G_1} + \frac{1}{G_2} + \cdots + \frac{1}{G_n}</math>.
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| For a special case of two resistors in series, the total conductance is equal to:
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| :<math>G_{total} = \frac{G_1 G_2}{G_1+G_2}.</math>
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| === Inductors ===
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| [[Inductor]]s follow the same law, in that the total [[inductance]] of non-coupled inductors in series is equal to the sum of their individual inductances:
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| [[Image:Inductors in series.svg|A diagram of several inductors, connected end to end, with the same amount of current going through each.]]
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| :<math>L_\mathrm{total} = L_1 + L_2 + \cdots + L_n</math>
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| However, in some situations it is difficult to prevent adjacent inductors from influencing each other, as the magnetic field of one device couples with the windings of its neighbours. This influence is defined by the mutual inductance M. For example, if two inductors are in series, there are two possible equivalent inductances depending on how the magnetic fields of both inductors influence each other.
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| When there are more than two inductors, the mutual inductance between each of them and the way the coils influence each other complicates the calculation. For a larger number of coils the total combined inductance is given by the sum of all mutual inductances between the various coils including the mutual inductance of each given coil with itself, which we term self-inductance or simply inductance. For three coils, there are six mutual inductances <math>M_{12}</math>, <math>M_{13}</math>, <math>M_{23}</math> and <math>M_{21}</math>, <math>M_{31}</math> and <math>M_{32}</math>. There are also the three self-inductances of the three coils: <math>M_{11}</math>, <math>M_{22}</math> and <math>M_{33}</math>.
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| Therefore
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| :<math>L_\mathrm{total} = (M_{11} + M_{22} + M_{33}) + (M_{12} + M_{13} + M_{23}) + (M_{21} + M_{31} + M_{32})</math>
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| By reciprocity <math>M_{ij}</math> = <math>M_{ji}</math> so that the last two groups can be combined. The first three terms represent the sum of the self-inductances of the various coils. The formula is easily extended to any number of series coils with mutual coupling. The method can be used to find the self-inductance of large coils of wire of any cross-sectional shape by computing the sum of the mutual inductance of each turn of wire in the coil with every other turn since in such a coil all turns are in series.
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| {{anchor|Cseries}}
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| === Capacitors ===
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| ''See also [[Capacitor#Networks|Capacitor networks]]''<br />
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| [[Capacitor]]s follow the same law using the reciprocals. The total [[capacitance]] of capacitors in series is equal to the reciprocal of the sum of the [[Multiplicative inverse|reciprocals]] of their individual capacitances:
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| [[Image:Capacitors in series.svg|A diagram of several capacitors, connected end to end, with the same amount of current going through each.]]
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| :<math>\frac{1}{C_\mathrm{total}} = \frac{1}{C_1} + \frac{1}{C_2} + \cdots + \frac{1}{C_n}</math>.
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| ===Switches===
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| Two or more [[switch]]es in series form a [[Logical conjunction|logical AND]]; the circuit only carries current if all switches are 'on'. See [[AND gate]].
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| ===Cells and batteries===
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| A [[Battery (electricity)|battery]] is a collection of [[electrochemical cell]]s. If the cells are connected in series, the [[voltage]] of the battery will be the sum of the cell voltages. For example, a 12 volt [[car battery]] contains six 2-volt cells connected in series. Some vehicles, such as trucks, have two 12 volt batteries in series to feed the 24 volt system.
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| == Parallel circuits ==<!-- This section is linked from [[Leyden jar]] -->
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| If two or more components are connected in parallel they have the same potential difference ([[voltage]]) across their ends. The potential differences across the components are the same in magnitude, and they also have identical polarities. The same voltage is applicable to all circuit components connected in parallel. The total current is the sum of the currents through the individual components, in accordance with [[Kirchhoff's circuit laws#Kirchhoff's current law (KCL)|Kirchhoff’s current law]].
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| {{anchor|Rparallel}}
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| ===Voltage===
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| In a parallel circuit the voltage is the same for all elements.
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| :<math>
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| V = V_1 = V_2 = \ldots = V_n
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| </math> | |
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| {{anchor|Rparallel}}
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| ===Resistors===
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| The current in each individual resistor is found by [[Ohm's law]]. Factoring out the voltage gives
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| :<math>I_\mathrm{total} = V\left(\frac{1}{R_1} + \frac{1}{R_2} + \cdots + \frac{1}{R_n}\right)</math>.
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| To find the total [[Electrical resistance|resistance]] of all components, add the [[Multiplicative inverse|reciprocals]] of the resistances <math>R_i</math> of each component and take the reciprocal of the sum. Total resistance will always be less than the value of the smallest resistance:
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| [[Image:Resistors in parallel.svg|A diagram of several resistors, side by side, both leads of each connected to the same wires.]]
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| :<math>\frac{1}{R_\mathrm{total}} = \frac{1}{R_1} + \frac{1}{R_2} + \cdots + \frac{1}{R_n}</math>.
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| For only two resistors, the unreciprocated expression is reasonably simple:
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| :<math>R_\mathrm{total} = \frac{R_1R_2}{R_1+R_2} .</math>
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| This sometimes goes by the mnemonic "product over sum".
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| For ''N'' equal resistors in parallel, the reciprocal sum expression simplifies to:
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| :<math>\frac{1}{R_\mathrm{total}} = \frac{1}{R} \times N</math>.
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| and therefore to:
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| :<math>{R_\mathrm{total}} = \frac{R}{N}</math>.
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| To find the [[current (electricity)|current]] in a component with resistance <math>R_i</math>, use Ohm's law again:
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| :<math>I_i = \frac{V}{R_i}\,</math>.
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| The components divide the current according to their reciprocal resistances, so, in the case of two resistors,
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| :<math>\frac{I_1}{I_2} = \frac{R_2}{R_1}</math>.
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| An old term for devices connected in parallel is ''multiple'', such as a multiple connection for [[arc lamp]]s.
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| Since electrical conductance <math>G</math> is reciprocal to resistance, the expression for total conductance of a parallel circuit of resistors reads:
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| :<math>{G_\mathrm{total}} = {G_1} + {G_2} + \cdots + {G_n}</math>.
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| The relations for total conductance and resistance stand in a complementary relationship: the expression for a series connection of resistances is the same as for parallel connection of conductances, and vice versa.
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| {{anchor|Lparallel}}
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| ===Inductors===
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| [[Inductor]]s follow the same law, in that the total [[inductance]] of non-coupled inductors in parallel is equal to the reciprocal of the sum of the reciprocals of their individual inductances:
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| [[Image:Inductors in parallel.svg|A diagram of several inductors, side by side, both leads of each connected to the same wires.]]
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| :<math>\frac{1}{L_\mathrm{total}} = \frac{1}{L_1} + \frac{1}{L_2} + \cdots + \frac{1}{L_n}</math>.
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| If the inductors are situated in each other's magnetic fields, this approach is invalid due to mutual inductance. If the mutual inductance between two coils in parallel is M, the equivalent inductor is:
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| :<math>\frac{1}{L_\mathrm{total}} = \frac{L_1+L_2-2M}{L_1L_2-M^2 } </math>
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| If <math>L_1=L_2</math>
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| :<math> L_{total} = \frac{L+M}{2}</math>
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| The sign of <math>M</math> depends on how the magnetic fields influence each other. For two equal tightly coupled coils the total inductance is close to that of each single coil. If the polarity of one coil is reversed so that M is negative, then the parallel inductance is nearly zero or the combination is almost non-inductive. It is assumed in the "tightly coupled" case M is very nearly equal to L. However, if the inductances are not equal and the coils are tightly coupled there can be near short circuit conditions and high circulating currents for both positive and negative values of M, which can cause problems.
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| More than three inductors becomes more complex and the mutual inductance of each inductor on each other inductor and their influence on each other must be considered. For three coils, there are three mutual inductances <math>M_{12}</math>, <math>M_{13}</math> and <math>M_{23}</math>. This is best handled by matrix methods and summing the terms of the inverse of the <math>L</math> matrix (3 by 3 in this case).
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| The pertinent equations are of the form:
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| <math>v_{i}=\sum_{j} L_{i,j}\frac{di_{j}}{dt} </math>
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| {{anchor|Cparallel}}
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| === Capacitors ===
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| The total [[capacitance]] of capacitors in parallel is equal to the sum of their individual capacitances:
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| [[Image:Capacitors in parallel.svg|A diagram of several capacitors, side by side, both leads of each connected to the same wires.]]
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| :<math>C_\mathrm{total} = C_1 + C_2 + \cdots + C_n</math>.
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| The working voltage of a parallel combination of capacitors is always limited by the smallest working voltage of an individual capacitor.
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| ===Switches===
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| Two or more [[switch]]es in parallel form a [[Logical disjunction|logical OR]]; the circuit carries current if at least one switch is 'on'. See [[OR gate]].
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| ===Cells and batteries===
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| If the cells of a battery are connected in parallel, the battery voltage will be the same as the cell voltage but the current supplied by each cell will be a fraction of the total current. For example, if a battery contains four cells connected in parallel and delivers a current of 1 [[ampere]], the current supplied by each cell will be 0.25 ampere. Parallel-connected batteries were widely used to power the [[Vacuum tube|valve]] filaments in [[portable radio]]s but they are now rare. Some solar electric systems have batteries in parallel to increase the storage capacity; a close approximation of total amp-hours is the sum of all batteries in parallel.
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| == Combining conductances ==
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| From [[Kirchhoff's circuit laws]] we can deduce the rules for combining conductances. For two conductances <math>G_1</math> and <math>G_2</math> in parallel the voltage across them is the same and from Kirchhoff's Current Law the total current is
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| : <math>I_{Eq} = I_1 + I_2.\ \,</math>
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| Substituting Ohm's law for conductances gives
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| : <math>G_{Eq} V = G_1 V + G_2 V\ \,</math>
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| and the equivalent conductance will be,
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| : <math>G_{Eq} = G_1 + G_2.\ \,</math>
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| For two conductances <math>G_1</math> and <math>G_2</math> in series the current through them will be the same and Kirchhoff's Voltage Law tells us that the voltage across them is the sum of the voltages across each conductance, that is,
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| : <math>V_{Eq} = V_1 + V_2.\ \,</math>
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| Substituting Ohm's law for conductance then gives,
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| : <math>\frac {I}{G_{Eq}} = \frac {I}{G_1} + \frac {I}{G_2}</math>
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| which in turn gives the formula for the equivalent conductance, | |
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| : <math>\frac {1}{G_{Eq}} = \frac {1}{G_1} + \frac {1}{G_2}.</math>
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| This equation can be rearranged slightly, though this is a special case that will only rearrange like this for two components.
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| : <math>G_{Eq} = \frac{G_1 G_2}{G_1+G_2}.</math>
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| ==Notation==
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| The value of two components in parallel is often represented in equations by two vertical lines "||", borrowing the [[Parallel (geometry)#Symbol|parallel lines notation from geometry]].<ref>http://www.en-genius.net/includes/files/avt_120406.pdf</ref><ref>http://tex.stackexchange.com/questions/37912/how-to-draw-the-parallel-circuits-sign</ref>
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| :<math>
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| R_\mathrm{eq} = R_1 \| R_2 = {R_1 R_2 \over R_1 + R_2}
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| </math>
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| This simplifies expressions that would otherwise become complicated by expansion of the terms. For instance, the expression <math>R_1 \| R_2 \| R_3</math> refers to 3 resistors in parallel, while the expanded expression is <math>\frac{R_1 R_2 R_3}{\left( R_2 + R_1 \right) R_3 + R_1 R_2}</math>.
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| ==Applications==
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| Most common application of series circuit in consumer electronics is the 9 volt block battery, the fire alarm battery, which is internally built of six batteries, 1.5 volts each.
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| Series circuits were formerly used for lighting in [[electric multiple unit]] trains. For example, if the supply voltage was 600 volts there might be eight 70-volt bulbs in series (total 560 volts) plus a [[resistor]] to drop the remaining 40 volts. Series circuits for train lighting were superseded, first by [[motor-generator]]s, then by [[Solid state (electronics)|solid state]] devices.
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| Series resistance can also be applied to the arrangement of blood vessels within a given organ. Each organ is supplied by a large artery, smaller arteries, arterioles, capillaries, and veins arranged in series. The total resistance is the sum of the individual resistances, as expressed by the following equation: R<sub>total</sub> = R<sub>artery</sub> + R<sub>arterioles</sub> + R<sub>capillaries</sub>. The largest proportion of resistance in this series is contributed by the arterioles.<ref name="BRS">''Board Review Series: Physiology'' by Linda S. Costanzo pg. 74</ref>
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| Parallel resistance is illustrated by the [[circulatory system]]. Each organ is supplied by an artery that branches off the [[aorta]]. The total resistance of this parallel arrangement is expressed by the following equation: 1/R<sub>total</sub> = 1/R<sub>a</sub> + 1/R<sub>b</sub> + ... 1/R<sub>n</sub>. R<sub>a</sub>, R<sub>b</sub>, and R<sub>n</sub> are the resistances of the renal, hepatic, and other arteries respectively. The total resistance is less than the resistance of any of the individual arteries.<ref name="BRS"/>
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| == See also ==
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| *[[network analysis (electrical circuits)]]
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| *[[Wheatstone bridge]]
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| *[[Y-Δ transform]]
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| *[[Voltage divider]]
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| *[[Current divider]]
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| *[[Electrical impedance#Combining impedances|Combining impedances]]
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| *[[Equivalent impedance transforms]]
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| *[[Resistance distance]]
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| ==Notes==
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| {{Reflist}}
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| ==References==
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| * Resnick, Robert and Halliday, David (1966), ''Physics'', Vol I and II, Combined edition, Wiley International Edition, Library of Congress Catalog Card No. 66-11527
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| * Smith, R.J. (1966), ''Circuits, Devices and Systems'', Wiley International Edition, New York. Library of Congress Catalog Card No. 66-17612
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| * Williams, Tim, ''The Circuit Designer's Companion'', Butterworth-Heinemann, 2005 ISBN 0-7506-6370-7.
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| == External links ==
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| * [http://www.autoshop101.com/trainmodules/elec_circuits/circ114.html Series circuits – see page 14 and onwards]
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| * [http://www.autoshop101.com/trainmodules/elec_circuits/circ122.html Parallel circuit – see page 22 and onwards]
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| *[http://arxiv.org/a/khan_s_1 Sameen Ahmed Khan], [http://www.ias.ac.in/resonance/Volumes/17/05/0468-0475.pdf How many equivalent resistances?], [http://www.ias.ac.in/resonance/ Resonance Journal of Science Education], Vol. 17, No. 5, 468-475 (May 2012).
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| [[Category:Electronic circuits]]
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| [[ca:Circuit en sèrie]]
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| [[de:Reihenschaltung]]
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| [[es:Circuito paralelo]]
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| [[es:Circuito en serie]]
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| [[fr:Circuit en série]]
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| [[pt:Circuito série]]
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| [[no:Seriekobling]]
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If you were younger, perhaps we were 1 of those lucky persons who didnt need weight reduction help. Maybe we were chasing kids, working at an outside job, cooking, cleaning plus living an active lifestyle. Its not which guys over 50 plus post-menopausal females are not active. However usually they are less active. This will be due to physical limitations, like arthritis, or considering they have merely gotten employed to a more sedentary life-style in retirement or if they are nonetheless working.
What weight would I be pleased with when my ideal is too low? This really is a weight that's not the ideal, but it would satisfy us; be within a healthy weight range plus will be more reasonable given the present lifestyle. I like to compare my clients' goals to the bmi chart for the healthiest weight ranges for their height. Here's one more path to take green, BMI green, that is (The bmi chart is colored coded with green because the healthy weight ranges. Take a guess the color for unhealthiest?) Scroll down for a link to a bmi chart where I give all of the hyperlinks.
A BMI calculator shows whether you're underweight, regular, obese, or overweight. Keep in your mind, though, it is a rough estimate of the ratio of the weight and height. Although the BMI is considered a body fat calculator, sometimes people that are muscular are not able to correctly gauge their body fat. Why behind this really is that muscle weight is heavier than fat. So, they might weigh more for their height, yet it really is muscle weight plus not fat at all. However, for those that are barely active, the BMI calculator is a remarkable tool in gauging their body fat.
Lets say an adult male is 60 and weighs 200 pounds. According to this chart, his BMI would be 27.1, which puts him into the overweight category. If he loses 17 pounds, the same man, today at 183 pounds, would have a BMI of 24.8, which would put him in the general weight category.
Having sex using the missionary position assist to get pregnant- the time-proven 'man-on-top' position works with gravity to encourage semen flow toward the uterus to maximize the chance of the sperm uniting with the egg plus causing conception. One of the associated right tips on getting pregnant is -- following ejaculation, the female could stay on her back with her legs bent a few minutes to further maximize semen flow toward the uterus.
With my plan, you'll eat three food bmi chart women plus three snacks a day. Each individual will have a different number of calories which he or she could eat per day and nonetheless lose at least 1 pound per week (and more with exercise). You start with acquiring the BMI.
That is not to state which the changes in preference were big, with the age of the woman models rarely being above 25 years. Same used to the alternative measurements. During the 40 years in question the lowest Body Mass Index was 16 plus highest was 20, with the average being about middle in between (to calculate BMI visit this BMI Calculator). Same applied to Waist-to-Hip ratio which stayed in the range of .57 to .73.
There are too little fluctuations in the BMI thresholds for the both sexes, plus for different races. For instance, health practice suggests which the grade of normal body mass chart should be lower for people of oriental origin. If you've any worries or concerns about a Body Mass Index then see the doctor.