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| The '''Cavendish experiment''', performed in 1797–98 by British scientist [[Henry Cavendish]], was the first experiment to measure the force of [[Gravitation|gravity]] between [[mass]]es in the laboratory,<ref>[http://books.google.com/books?id=ZrloHemOmUEC&pg=PA355 Boys 1894] p. 355</ref> and the first to yield accurate values for the [[gravitational constant]].<ref>[http://books.google.com/books?id=DgTALFa3sa4C&pg=PA385 Encyclopædia Britannica 1910] p. 385 'The aim [of experiments like Cavendish's] may be regarded either as the determination of the mass of the Earth,...conveniently expressed...as its "mean density", or as the determination of the "gravitation constant", G'. Cavendish's experiment is generally described today as a measurement of G (Clotfelter 1987 p. 210).</ref><ref>Many sources incorrectly state that this was the first measurement of '''''G''''' (or the Earth's density); for instance: {{Cite book|last = Feynman|first = Richard P.|publisher = California Institute of Technology|year = |isbn = 9780465025626|location = Pasadena, California|url = http://www.feynmanlectures.caltech.edu/I_07.html#Ch1-S1|series = The Feynman lectures on physics|volume = Volume I|title = mainly mechanics, radiation and heat|publication-date = 2013|origyear = 1963|chapterurl = http://www.feynmanlectures.caltech.edu/I_07.html|chapter = 7. The Theory of Gravitation|at = 7–6 Cavendish’s experiment|accessdate = December 9, 2013}}
| | When you were younger, possibly we were one of those fortunate persons whom didnt need fat reduction help. Maybe you were chasing kids, working at an outside job, cooking, cleaning plus living an active lifestyle. Its not which men over 50 and post-menopausal ladies are not active. But usually they are less active. This might be considering of physical limitations, such as arthritis, or considering they have really gotten chosen to a more sedentary lifestyle in retirement or if they are still working.<br><br>BMI can be calculated inside metric or imperial measurements. There is a slight variation between your 2 equations, however, the outcome is exact enough for health assessment purposes. BMI may be calculated utilizing a [http://safedietplansforwomen.com/bmi-chart bmi chart], an online BMI calculator, or manually utilizing the BMI equation. The results, that are taken to two decimal places, are the same for each. The BMI equation is obtainable in metric or imperial measurements, plus there is a quite slight variation in the two figures.<br><br>There seem to be a consistent preference amidst bmi chart men males for a female BMI index about 20. With BMI above 25 being considered too excellent and under 15 being too slim.<br><br>Another benefit of green leafy veggies is that they provide phytonutrients, that are nutrients mandatory for sustaining human health by preventing cell damage, preventing cancer mobile replication plus lowering cholesterol degrees. They also are a source of vitamins C, E, E plus numerous of the B vitamins. Dark green leafy greens contain tiny amounts of omega-3 fats.<br><br>Anorexia nervosa is an emotional disorder where the primary focus may be on food / the avoidance of food but it additionally deals with unhealthy ways of gaining perfection along with a desire to control factors. In a society that associates unreasonable thinness with beauty, there has been a marked escalation in the amount of young adolescent females with anorexia. Many of them die due to starvation-related causes, suffer from bodily problems, or end up committing suicide. It is important to treat such people with psychotherapy, family therapy, plus medication.<br><br>Example 1: A healthy, normally-proportioned 5-foot-tall individual bmi chart women weighs 100 pounds. What would you expect a 6-foot-tall person to weigh according to BMI?<br><br>To make sure all these measurements are exact, you need to be inside .5 a centimeter, or a .25 centimeter, if possible. Men and women measure different parts of their body.<br><br>These Television leaders felt which Isagenix was so far ahead in their thinking plus their results, and were impressed enough to give this organization the greatest advertising anybody may ever obtain plus which is free advertising. |
| There were previous measurements, chiefly Bouguer (1740) and Maskelyne (1774), but they were very inaccurate ([http://ebooks.library.ualberta.ca/local/meandensityofear00poynuoft Poynting 1894])([http://books.google.com/books?id=DgTALFa3sa4C&pg=PA385 Encyclopædia Britannica 1910]).
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| </ref> Because of the unit conventions then in use, the gravitational constant does not appear explicitly in Cavendish's work. Instead, the result was originally expressed as the [[specific gravity]] of the Earth,<ref>Clotfelter 1987, p. 210</ref> or equivalently the mass of the Earth; and were the first accurate values for these geophysical constants. The experiment was devised sometime before 1783<ref>[http://books.google.com/books?id=EUoLAAAAIAAJ&pg=PA336&sig=--1AlZ9rl_0AEL7h73LZvtK01S4 McCormmach & Jungnickel 1996], p.336: A 1783 letter from Cavendish to Michell contains '...the earliest mention of weighing the world'. Not clear whether 'earliest mention' refers to Cavendish or Michell.</ref> by geologist [[John Michell]],<ref>[http://books.google.com/books?id=O58mAAAAMAAJ&pg=PA59 Cavendish 1798], p. 59 Cavendish gives full credit to Michell for devising the experiment</ref> who constructed a [[torsion balance]] apparatus for it. However, Michell died in 1793 without completing the work, and after his death the apparatus passed to Francis John Hyde Wollaston and then to Henry Cavendish, who rebuilt the apparatus but kept close to Michell's original plan. Cavendish then carried out a series of measurements with the equipment, and reported his results in the ''[[Philosophical Transactions of the Royal Society]]'' in 1798.<ref>Cavendish, H. 'Experiments to determine the Density of the Earth', ''Philosophical Transactions of the Royal Society of London'', (part II) '''88''' p.469-526 (21 June 1798), reprinted in [http://books.google.com/books?id=O58mAAAAMAAJ&pg=PA59 Cavendish 1798]</ref>
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| ==The experiment==
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| The apparatus constructed by Cavendish was a [[torsion balance]] made of a six-foot (1.8 m) wooden rod suspended from a wire, with a {{convert|2|in|0|adj=on}} diameter {{convert|1.61|lb|adj=on}} [[lead]] sphere attached to each end. Two {{convert|12|in|adj=on}} {{convert|348|lb|adj=on}} lead balls were located near the smaller balls, about {{convert|9|in}} away, and held in place with a separate suspension system.<ref>[http://books.google.com/books?id=O58mAAAAMAAJ&pg=PA59 Cavendish 1798], p.59</ref> The experiment measured the faint gravitational attraction between the small balls and the larger ones.
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| [[File:Cavendish Experiment.png|thumb|left|250px|Vertical section drawing of Cavendish's torsion balance instrument including the building in which it was housed. The large balls were hung from a frame so they could be rotated into position next to the small balls by a pulley from outside. Figure 1 of Cavendish's paper.]]
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| [[File:CavendishSchematic111.jpg|thumb|left|250px|Detail showing torsion balance arm (''m''), large ball (''W''), small ball (''x''), and isolating box (''ABCDE'').]]
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| The two large balls were positioned on alternate sides of the horizontal wooden arm of the balance. Their mutual attraction to the small balls caused the arm to rotate, twisting the wire supporting the arm. The arm stopped rotating when it reached an angle where the twisting force of the wire balanced the combined gravitational force of attraction between the large and small lead spheres. By measuring the angle of the rod, and knowing the twisting force ([[torque]]) of the wire for a given angle, Cavendish was able to determine the force between the pairs of masses. Since the gravitational force of the Earth on the small ball could be measured directly by weighing it, the ratio of the two forces allowed the density of the earth to be calculated, using [[Newton's law of universal gravitation|Newton's law of gravitation]].
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| Cavendish found that the Earth's density was 5.448 ± 0.033 times that of water (due to a simple arithmetic error, found in 1821 by [[Francis Baily]], the erroneous value 5.48 ± 0.038 appears in his paper).<ref name="Poynting 1894">[http://books.google.com/books?id=dg0RAAAAIAAJ&pg=PA45 Poynting 1894], p.45</ref>
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| To find the wire's [[Torsion spring#Torsion coefficient|torsion coefficient]], the torque exerted by the wire for a given angle of twist, Cavendish timed the natural [[Torsion spring#Torsional harmonic oscillators|oscillation period]] of the balance rod as it rotated slowly clockwise and counterclockwise against the twisting of the wire. The period was about 20 minutes. The torsion coefficient could be calculated from this and the mass and dimensions of the balance. Actually, the rod was never at rest; Cavendish had to measure the deflection angle of the rod while it was oscillating.<ref>[http://books.google.com/books?id=O58mAAAAMAAJ&pg=PA64 Cavendish 1798], p.64</ref>
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| Cavendish's equipment was remarkably sensitive for its time.<ref name="Poynting 1894"/> The force involved in twisting the torsion balance was very small, 1.74 x 10<sup>–7</sup> N,<ref>[http://books.google.com/books?id=ZrloHemOmUEC&pg=PA357 Boys 1894] p.357</ref> about 1/50,000,000 of the weight of the small balls<ref>[http://books.google.com/books?id=O58mAAAAMAAJ&pg=PA60 Cavendish 1798] p. 60</ref> or roughly the weight of a large grain of sand.<ref>A 2 mm sand grain weighs ~13 mg. {{cite web|last=Theodoris|first=Marina|year=2003|url=http://hypertextbook.com/facts/2003/MarinaTheodoris.shtml|title=Mass of a Grain of Sand|work=The Physics Factbook|accessdate=2013-12-30}}</ref> To prevent air currents and temperature changes from interfering with the measurements, Cavendish placed the entire apparatus in a wooden box about {{convert|2|ft|m}} thick, {{convert|10|ft|m}} tall, and {{convert|10|ft|m}} wide, all in a closed shed on his estate. Through two holes in the walls of the shed, Cavendish used telescopes to observe the movement of the torsion balance's horizontal rod. The motion of the rod was only about {{convert|0.16|in}}.<ref>[http://books.google.com/books?id=O58mAAAAMAAJ&pg=PA99 Cavendish 1798], p. 99, Result table, (scale graduations = 1/20 in ≈ 1.3 mm) The total deflection shown in most trials was twice this since he compared the deflection with large balls on opposite sides of the balance beam.</ref> Cavendish was able to measure this small deflection to an accuracy of better than one hundredth of an inch using [[vernier scale]]s on the ends of the rod.<ref>[http://books.google.com/books?id=O58mAAAAMAAJ&pg=PA63 Cavendish 1798], p.63</ref>
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| Cavendish's accuracy was not exceeded until [[C. V. Boys]]' experiment in 1895. In time, Michell's torsion balance became the dominant technique for measuring the [[gravitational constant|gravitational constant (''G'')]], and most contemporary measurements still use variations of it. This is why Cavendish's experiment became ''the'' Cavendish experiment.<ref>[http://books.google.com/books?id=EUoLAAAAIAAJ&pg=PA341&sig=--1AlZ9rl_0AEL7h73LZvtK01S4 McCormmach & Jungnickel 1996], p.341</ref>
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| ==Whether Cavendish determined G==
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| The formulation of [[Newton's law of universal gravitation|Newtonian gravity]] in terms of a gravitational constant did not become standard until long after Cavendish's time. Indeed, one of the first references to ''G'' is in 1873, 75 years after Cavendish's work.<ref>Cornu, A. and Baille, J. B. (1873), Mutual determination of the constant of attraction and the mean density of the earth, ''C. R. Acad. Sci.'', Paris Vol. 76, 954-958.</ref> Cavendish expressed his result in terms of the density of the Earth, and he referred to his experiment in correspondence as 'weighing the world'. Later authors reformulated his results in modern terms.<ref>[http://books.google.com/books?id=ZrloHemOmUEC&pg=PA353 Boys 1894], p.330 In this lecture before the Royal Society, Boys introduces G and argues for its acceptance</ref><ref>[http://books.google.com/books?id=dg0RAAAAIAAJ&pg=PA4 Poynting 1894], p.4</ref><ref>[http://books.google.com/books?id=O58mAAAAMAAJ&pg=PA1 MacKenzie 1900], p.vi</ref> thus:
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| :<math>G = g\frac{R_\text{earth}^2}{M_\text{earth}} = \frac{3g}{4\pi R_\text{earth}\rho_\text{earth}}\,</math>
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| After converting to [[SI]] units, Cavendish's value for the Earth's density, 5.448 g cm<sup>−3</sup>, gives
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| :{{math|1=''G'' = 6.74 × 10<sup>−11</sup> m<sup>3</sup> kg<sup>−1</sup> s<sup>−2</sup>}},
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| which differs by only 1% from the currently accepted value: 6.67428 × 10<sup>−11</sup> m<sup>3</sup> kg<sup>−1</sup> s<sup>−2</sup>.
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| For this reason, historians of science have argued that Cavendish did not measure the gravitational constant.<ref>Clotfelter 1987</ref><ref name="McCormmach & Jungnickel 1996">[http://books.google.com/books?id=EUoLAAAAIAAJ&pg=PA336&sig=--1AlZ9rl_0AEL7h73LZvtK01S4 McCormmach & Jungnickel 1996], p.337</ref><ref>[http://www.public.iastate.edu/~lhodges/Michell.htm Hodges 1999]</ref><ref>Lally 1999</ref>
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| Physicists, however, often use units where the gravitational constant takes a different form. The [[Gaussian gravitational constant]] used in space dynamics is a defined constant, and the Cavendish experiment can be considered as a measurement of the [[astronomical unit]].
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| In Cavendish's time, physicists used the same units for mass and weight, in effect taking <math>g</math> as a standard acceleration. Then, since <math>R_\text{earth}</math> was known, <math>\rho_\text{earth}</math> played the role of an inverse gravitational constant. The density of the Earth was hence a much sought-after quantity at the time, and there had been earlier attempts to measure it, such as the [[Schiehallion experiment]] in 1774.
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| For these reasons, physicists generally do credit Cavendish with the first measurement of the gravitational constant.<ref>{{Cite book|last=Halliday|first=David|last2=Resnick|first2=Robert|title=Fundamentals of Physics|year=1993|publisher=John Wiley & Sons|isbn=978-0-471-14731-2|page=418|url=http://books.google.com/?id=-AjnmJHPiKMC&pg=PA418|postscript=<!--None-->|accessdate=2013-12-30}} 'The apparatus used in 1798 by Henry Cavendish to measure the gravitational constant'</ref><ref>{{Cite document|last=Feynman|first=Richard P.|title=Lectures on Physics, Vol.1|year=1963|publisher=Addison-Wesley|pages=6–7|url=http://www.feynmanlectures.caltech.edu/I_07.html#Ch7-S6|ISBN=0-201-02116-1|postscript=<!--None-->}} 'Cavendish claimed he was weighing the Earth, but what he was measuring was the coefficient G...'</ref><ref>{{Cite document|last=Feynman|first=Richard P.|title=The Character of Physical Law|year=1967|publisher=MIT Press|pages=28|url=http://www.feynmanlectures.caltech.edu/I_07.html#Ch7-S6|ISBN=0-262-56003-8|postscript=<!--None-->}} 'Cavendish was able to measure the force, the two masses, and the distance, and thus determine the gravitational constant G'</ref><ref name=HarvLect>{{cite web|title=Cavendish Experiment, Harvard Lecture Demonstrations, Harvard Univ|url=http://sciencedemonstrations.fas.harvard.edu/icb/icb.do?keyword=k16940&pageid=icb.page80669&pageContentId=icb.pagecontent277503&state=maximize&view=view.do&viewParam_name=indepth.html#a_icb_pagecontent277503|accessdate=2007-08-26|postscript=<!--None-->|accessdate=2013-12-30}}. '[the torsion balance was]...modified by Cavendish to measure G.'</ref><ref>{{Cite book|last=Shectman|first=Jonathan|title=Groundbreaking Experiments, Inventions, and Discoveries of the 18th Century|year=2003|publisher=Greenwood|pages=xlvii|url=http://books.google.com/?id=SsbChdIiflsC&pg=PAxlvii|isbn=978-0-313-32015-6|postscript=<!--None-->|accessdate=2013-12-30}} 'Cavendish calculates the gravitational constant, which in turn gives him the mass of the earth...'</ref>
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| ==Derivation of G and the Earth's mass==
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| :''For the definitions of terms, see the drawing below and the table at the end of this section.''
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| The following is not the method Cavendish used, but shows how modern physicists would calculate the results from his experiment.<ref name=HarvLect/><ref>[http://books.google.com/books?id=dg0RAAAAIAAJ&pg=PA41 Poynting 1894], p.41</ref><ref>Clotfelter 1987 p.212 explains Cavendish's original method of calculation</ref> From [[Torsion spring#Torsion coefficient|Hooke's law]], the [[torque]] on the torsion wire is proportional to the deflection angle ''<big><math>\theta</math></big>'' of the balance. The torque is ''<big><math>\kappa\theta</math></big>'' where ''<big><math>\kappa</math></big>'' is the [[torsion coefficient]] of the wire. However, the torque can also be written as a product of the attractive forces between the balls and the distance to the suspension wire. Since there are two pairs of balls, each experiencing force ''F'' at a distance ''L / 2'' from the axis of the balance, the torque is ''LF''. Equating the two formulas for torque gives the following:
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| :<math>\kappa\theta\ = LF \,</math>
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| For ''F'', [[Isaac Newton|Newton]]'s [[law of universal gravitation]] is used to express the attractive force between the large and small balls:
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| [[File:Cavendish Torsion Balance Diagram.svg|thumb|220px|Diagram of torsion balance]]
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| :<math>F = \frac{G m M}{r^2}\,</math>
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| Substituting F into the first equation above gives
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| :<math>\kappa\theta\ = L\frac{GmM}{r^2} \qquad\qquad\qquad(1)\,</math>
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| To find the torsion coefficient (<math>\kappa\,</math>) of the wire, Cavendish measured the natural [[Resonance|resonant]] [[Torsion spring#Torsional harmonic oscillators|oscillation period]] ''T'' of the torsion balance:
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| :<math>T = 2\pi\sqrt{I/\kappa}</math>
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| Assuming the mass of the torsion beam itself is negligible, the [[moment of inertia]] of the balance is just due to the small balls:
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| :<math>I = m(L/2)^2 + m(L/2)^2 = 2m(L/2)^2 = mL^2/2\,</math>,
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| and so: | |
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| :<math>T = 2\pi\sqrt{\frac{mL^2}{2\kappa}}\,</math>
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| Solving this for ''<big><math>\kappa</math></big>'', substituting into (1), and rearranging for ''G'', the result is:
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| :<math>G = \frac{2 \pi^2 L r^2}{M T^2} \theta\,</math>
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| Once ''G'' has been found, the attraction of an object at the Earth's surface to the Earth itself can be used to calculate the Earth's mass and density:
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| :<math>mg = \frac{GmM_{earth}}{R_{earth}^2}\,</math>
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| :<math>M_{earth} = \frac{gR_{earth}^2}{G}\,</math>
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| :<math>\rho_{earth} = \frac{M_{earth}}{4 \pi R_{earth}^3/3} = \frac{3g}{4 \pi R_{earth} G}\,</math>
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| {|cellpadding="1" style="background:#F8F8F8;border:1px solid;"
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| |-
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| |colspan="3"|'''Definition of terms'''
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| |-
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| |width="80"|'''<big>SYMBOL</big>'''||'''<big>UNITS</big>'''||'''<big>DEFINITION</big>'''
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| |-
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| |width="80"|<math>\theta\,</math>|| style="width:100px;"|<math>\mbox{radians}\,</math>||Deflection of torsion balance beam from its rest position
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| |<math>F\,</math>||<math>\mbox{N}\,</math>||Gravitational force between masses M and m
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| |<math>G\,</math>||<math>\mbox{m}^3 {\mbox{kg}}^{-1} \mbox{s}^{-2}\,</math>||Gravitational constant
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| |-
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| |<math>m\,</math>||<math>\mbox{kg}\,</math>||Mass of small lead ball
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| |<math>M\,</math>||<math>\mbox{kg}\,</math>||Mass of large lead ball
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| |<math>r\,</math>||<math>\mbox{m}\,</math>||Distance between centers of large and small balls when balance is deflected
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| |<math>L\,</math>||<math>\mbox{m}\,</math>||Length of torsion balance beam between centers of small balls
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| |<math>\kappa\,</math>||<math>\mbox{N}\,\mbox{m}\,\mbox{radian}^{-1}\,</math>||Torsion coefficient of suspending wire
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| |<math>I\,</math>||<math>\mbox{kg}\,\mbox{m}^2\,</math>||Moment of inertia of torsion balance beam
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| |<math>T\,</math>||<math>\mbox{s}\,</math>||Period of oscillation of torsion balance
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| |<math>g\,</math>||<math>\mbox{m}\,\mbox{s}^{-2}\,</math>||Acceleration of gravity at the surface of the Earth
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| |<math>M_{earth}\,</math>||<math>\mbox{kg}\,</math>||Mass of the Earth
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| |<math>R_{earth}\,</math>||<math>\mbox{m}\,</math>||Radius of the Earth
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| |<math>\rho_{earth}\,</math>||<math>\mbox{kg}\,\mbox{m}^{-3}\,</math>||Density of the Earth
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| |}
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| == See also ==
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| {{Portal|Physics}}
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| * [[Schiehallion experiment]]
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| {{clear}}
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| ==Notes==
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| {{Reflist|30em}}
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| ==References==
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| * {{cite journal | author=Boys, C. Vernon | title=On the Newtonian constant of gravitation | journal=Nature | year=1894 | volume=50 | issue=1292 | pages=330–4 | url=http://books.google.com/?id=ZrloHemOmUEC&pg=PA353 | doi=10.1038/050330a0|bibcode = 1894Natur..50..330.|accessdate = 2013-12-30 }}
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| * {{Cite book | last=Cavendish | first=Henry | contribution=Experiments to Determine the Density of the Earth | year=1798 | editor-last=MacKenzie | editor-first=A. S. | title=Scientific Memoirs Vol.9: The Laws of Gravitation | publication-date=1900 | publisher=American Book Co. | pages=59–105 | url=http://books.google.com/?id=O58mAAAAMAAJ&pg=PA59 | postscript=<!--None--> | accessdate=2013-12-30 }} Online copy of Cavendish's 1798 paper, and other early measurements of gravitational constant.
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| * {{cite journal | author = Clotfelter, B. E. | title = The Cavendish experiment as Cavendish knew it | journal = American Journal of Physics | year = 1987 | volume = 55 | issue = 3 | pages = 210–213 | doi = 10.1119/1.15214|bibcode = 1987AmJPh..55..210C }} Establishes that Cavendish didn't determine G.
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| * {{cite journal | author = Falconer, Isobel | title = Henry Cavendish: the man and the measurement | journal = Measurement Science and Technology | year = 1999 | volume = 10 | issue = 6 | pages = 470–477 | doi = 10.1088/0957-0233/10/6/310 |bibcode = 1999MeScT..10..470F }}
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| *{{cite encyclopedia | title=Gravitation Constant and Mean Density of the Earth | encyclopedia=Encyclopædia Britannica, 11th Ed. | volume=12 | publisher=The Encyclopædia Britannica Co. | year=1910 | pages=385–389 | url=http://books.google.com/books?id=DgTALFa3sa4C&pg=PA385 | accessdate=2013-12-30 }}
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| * {{cite web | last=Hodges | first=Laurent | year=1999 | title=The Michell-Cavendish Experiment, faculty website, Iowa State Univ. | url=http://www.public.iastate.edu/~lhodges/Michell.htm | accessdate=2007-08-28 | accessdate=2013-12-30 }} Discusses Michell's contributions, and whether Cavendish determined G.
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| * {{cite journal | author = Lally, Sean P. | title = Henry Cavendish and the Density of the Earth | journal = The Physics Teacher | year = 1999 | volume = 37 | issue = 1 | pages = 34–37 | bibcode=1999PhTea..37...34L | doi = 10.1119/1.880145}}
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| * {{cite book
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| | last = McCormmach
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| | first = Russell
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| | coauthors = Jungnickel, Christa
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| | title = Cavendish
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| | location = Philadelphia, Pennsylvania
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| | publisher = [[American Philosophical Society]]
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| | year = 1996
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| | pages =
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| | url = http://books.google.com/?id=EUoLAAAAIAAJ
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| | isbn = 0-87169-220-1
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| | accessdate = 2013-12-30 }}
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| * {{cite book | last=Poynting | first=John H. | title=The Mean Density of the Earth: An essay to which the Adams prize was adjudged in 1893 | year=1894 | publisher=C. Griffin & Co. | location=London | url=http://books.google.com/?id=dg0RAAAAIAAJ | accessdate=2013-12-30 }} Review of gravity measurements since 1740.
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| *{{1911}}
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| ==External links==
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| * [http://web.archive.org/web/20080508011932/http://www.sas.org/tcs/weeklyIssues_2005/2005-07-01/feature1/index.html Sideways Gravity in the Basement, ''The Citizen Scientist'', July 1, 2005]. Homebrew Cavendish experiment, showing calculation of results and precautions necessary to eliminate wind and electrostatic errors.
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| * [http://www.physicscentral.com/explore/action/bigg.cfm "Big 'G'", Physics Central], retrieved Dec. 8, 2013. Experiment at Univ. of Washington to measure the gravitational constant using variation of Cavendish method. <!-- page captured by archive.is on 8 Dec 2013 -->
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| * [http://www.npl.washington.edu/eotwash/bigG "The Controversy over Newton's Gravitational Constant", Eöt-Wash Group, Univ. of Washington], retrieved Dec. 8, 2013. Discusses current state of measurements of '''''G'''''. <!-- page captured by archive.is on 2 Oct 2013 -->
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| * [http://www.scienceandsociety.co.uk/results.asp?image=10314095 Model of Cavendish's torsion balance], retrieved Aug. 28, 2007, at Science Museum, London.
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| * [http://www.juliantrubin.com/bigten/cavendishg.html Weighing the Earth] - background and experiment
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| {{DEFAULTSORT:Cavendish Experiment}}
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| [[Category:Physics experiments]]
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| [[Category:1790s in science]]
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| [[Category:1797 in science]]
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| [[Category:1798 in science]]
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When you were younger, possibly we were one of those fortunate persons whom didnt need fat reduction help. Maybe you were chasing kids, working at an outside job, cooking, cleaning plus living an active lifestyle. Its not which men over 50 and post-menopausal ladies are not active. But usually they are less active. This might be considering of physical limitations, such as arthritis, or considering they have really gotten chosen to a more sedentary lifestyle in retirement or if they are still working.
BMI can be calculated inside metric or imperial measurements. There is a slight variation between your 2 equations, however, the outcome is exact enough for health assessment purposes. BMI may be calculated utilizing a bmi chart, an online BMI calculator, or manually utilizing the BMI equation. The results, that are taken to two decimal places, are the same for each. The BMI equation is obtainable in metric or imperial measurements, plus there is a quite slight variation in the two figures.
There seem to be a consistent preference amidst bmi chart men males for a female BMI index about 20. With BMI above 25 being considered too excellent and under 15 being too slim.
Another benefit of green leafy veggies is that they provide phytonutrients, that are nutrients mandatory for sustaining human health by preventing cell damage, preventing cancer mobile replication plus lowering cholesterol degrees. They also are a source of vitamins C, E, E plus numerous of the B vitamins. Dark green leafy greens contain tiny amounts of omega-3 fats.
Anorexia nervosa is an emotional disorder where the primary focus may be on food / the avoidance of food but it additionally deals with unhealthy ways of gaining perfection along with a desire to control factors. In a society that associates unreasonable thinness with beauty, there has been a marked escalation in the amount of young adolescent females with anorexia. Many of them die due to starvation-related causes, suffer from bodily problems, or end up committing suicide. It is important to treat such people with psychotherapy, family therapy, plus medication.
Example 1: A healthy, normally-proportioned 5-foot-tall individual bmi chart women weighs 100 pounds. What would you expect a 6-foot-tall person to weigh according to BMI?
To make sure all these measurements are exact, you need to be inside .5 a centimeter, or a .25 centimeter, if possible. Men and women measure different parts of their body.
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