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Inverse-square law

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1363:(1666) in which he discussed, among other things, the relation between the height of the atmosphere and the barometric pressure at the surface. Since the atmosphere surrounds the Earth, which itself is a sphere, the volume of atmosphere bearing on any unit area of the Earth's surface is a truncated cone (which extends from the Earth's center to the vacuum of space; obviously only the section of the cone from the Earth's surface to space bears on the Earth's surface). Although the volume of a cone is proportional to the cube of its height, Hooke argued that the air's pressure at the Earth's surface is instead proportional to the height of the atmosphere because gravity diminishes with altitude. Although Hooke did not explicitly state so, the relation that he proposed would be true only if gravity decreases as the inverse square of the distance from the Earth's center. 33: 1262: 447:. Otherwise, if we want to calculate the attraction between massive bodies, we need to add all the point-point attraction forces vectorially and the net attraction might not be exact inverse square. However, if the separation between the massive bodies is much larger compared to their sizes, then to a good approximation, it is reasonable to treat the masses as a point mass located at the object's 1454: 685:, the effective origin is located far behind the beam aperture. If you are close to the origin, you don't have to go far to double the radius, so the signal drops quickly. When you are far from the origin and still have a strong signal, like with a laser, you have to travel very far to double the radius and reduce the signal. This means you have a stronger signal or have 704:, the inverse-square law is used to determine the “fall off” or the difference in illumination on a subject as it moves closer to or further from the light source. For quick approximations, it is enough to remember that doubling the distance reduces illumination to one quarter; or similarly, to halve the illumination increase the distance by a factor of 1.4 (the 1223:, in his 2020 paper "Non-Euclidean Newtonian Cosmology," elaborates on the behavior of force (F) and potential (Φ) within hyperbolic 3-space (H3). He illustrates that F and Φ obey the formulas F ∝ 1 / R^2 sinh^2(r/R) and Φ ∝ coth(r/R), where R and r represent the curvature radius and the distance from the focal point, respectively. 708:), and to double illumination, reduce the distance to 0.7 (square root of 1/2). When the illuminant is not a point source, the inverse square rule is often still a useful approximation; when the size of the light source is less than one-fifth of the distance to the subject, the calculation error is less than 1%. 1323:
Virtus autem illa, qua Sol prehendit seu harpagat planetas, corporalis quae ipsi pro manibus est, lineis rectis in omnem mundi amplitudinem emissa quasi species solis cum illius corpore rotatur: cum ergo sit corporalis imminuitur, & extenuatur in maiori spatio & intervallo, ratio autem huius
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The concept of the dimensionality of space, first proposed by Immanuel Kant, is an ongoing topic of debate in relation to the inverse-square law. Dimitria Electra Gatzia and Rex D. Ramsier, in their 2021 paper, argue that the inverse-square law pertains more to the symmetry in force distribution than
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both expounded gravitation in 1666 as an attractive force. Hooke's lecture "On gravity" was at the Royal Society, in London, on 21 March. Borelli's "Theory of the Planets" was published later in 1666. Hooke's 1670 Gresham lecture explained that gravitation applied to "all celestiall bodys" and added
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Hooke's gravitation was also not yet universal, though it approached universality more closely than previous hypotheses: See page 239 in Curtis Wilson (1989), "The Newtonian achievement in astronomy", ch.13 (pages 233–274) in "Planetary astronomy from the Renaissance to the rise of astrophysics: 2A:
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As for the power by which the Sun seizes or holds the planets, and which, being corporeal, functions in the manner of hands, it is emitted in straight lines throughout the whole extent of the world, and like the species of the Sun, it turns with the body of the Sun; now, seeing that it is corporeal,
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Sicut se habent spharicae superificies, quibus origo lucis pro centro est, amplior ad angustiorem: ita se habet fortitudo seu densitas lucis radiorum in angustiori, ad illamin in laxiori sphaerica, hoc est, conversim. Nam per 6. 7. tantundem lucis est in angustiori sphaerica superficie, quantum in
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If the moon and earth were not retained in their orbits by their animate force or some other equivalent, the earth would mount to the moon by a fifty-fourth part of their distance, and the moon fall towards the earth through the other fifty-three parts, and they would there meet, assuming, however,
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Just as spherical surfaces, for which the source of light is the center, from the wider to the narrower, so the density or fortitude of the rays of light in the narrower , towards the more spacious spherical surfaces, that is, inversely. For according to 6 & 7, there is as much light in the
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gets farther from the source, it is spread out over an area that is increasing in proportion to the square of the distance from the source. Hence, the intensity of radiation passing through any unit area (directly facing the point source) is inversely proportional to the square of the distance from
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depends on the strength of the light source and is constant with increasing distance, where a greater density of flux lines (lines per unit area) means a stronger energy field. The density of flux lines is inversely proportional to the square of the distance from the source because the surface area
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In a letter to Edmund Halley dated 20 June 1686, Newton wrote: "Bullialdus wrote that all force respecting ye Sun as its center & depending on matter must be reciprocally in a duplicate ratio of ye distance from ye center." See: I. Bernard Cohen and George E. Smith, ed.s,
259: 345: 715:(Φ) for indirectly ionizing radiation with increasing distance from a point source can be calculated using the inverse-square law. Since emissions from a point source have radial directions, they intercept at a perpendicular incidence. The area of such a shell is 4π 849:
would decrease by 6.02 dB per doubling of distance. When referring to measurements of power quantities, a ratio can be expressed as a level in decibels by evaluating ten times the base-10 logarithm of the ratio of the measured quantity to the reference value.
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Within the realm of non-Euclidean geometries and general relativity, deviations from the inverse-square law might not stem from the law itself but rather from the assumption that the force between bodies depends instantaneously on distance, contradicting
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The force of attraction or repulsion between two electrically charged particles, in addition to being directly proportional to the product of the electric charges, is inversely proportional to the square of the distance between them; this is known as
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The gravitational attraction force between two point masses is directly proportional to the product of their masses and inversely proportional to the square of their separation distance. The force is always attractive and acts along the line joining
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the principles that the gravitating power decreases with distance and that in the absence of any such power bodies move in straight lines. By 1679, Hooke thought gravitation had inverse square dependence and communicated this in a letter to
751:). At large distances from the source (compared to the size of the source), this power is distributed over larger and larger spherical surfaces as the distance from the source increases. Since the surface area of a sphere of radius 171: 178: 1899:
If two stones were placed in any part of the world near each other, and beyond the sphere of influence of a third cognate body, these stones, like two magnetic needles, would come together in the intermediate point,
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it becomes weaker and attenuated at a greater distance or interval, and the ratio of its decrease in strength is the same as in the case of light, namely, the duplicate proportion, but inversely, of the distances .
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Note: Both Kepler and William Gilbert had nearly anticipated the modern conception of gravity, lacking only the inverse-square law in their description of "gravitas". On page 4 of chapter 1, Introductio, of
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Gravity is a mutual affection between cognate bodies towards union or conjunction (similar in kind to the magnetic virtue), so that the earth attracts a stone much rather than the stone seeks the earth.
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Every corporeal substance, so far forth as it is corporeal, has a natural fitness for resting in every place where it may be situated by itself beyond the sphere of influence of a body cognate with it.
1103: 881:, the decrease is still 6.02 dB, since dB represents an intensity ratio. The pressure ratio (as opposed to power ratio) is not inverse-square, but is inverse-proportional (inverse distance law): 584: 470:'s solution for circular motion (motion in a straight line pulled aside by the central force). Indeed, Bullialdus maintained the sun's force was attractive at aphelion and repulsive at perihelion. 1458: 1254:
stating that "the latitude of a uniformly difform movement corresponds to the degree of the midpoint" and used this method to study the quantitative decrease in intensity of illumination in his
1981: 1315:(1605–1694) refuted Johannes Kepler's suggestion that "gravity" weakens as the inverse of the distance; instead, Bullialdus argued, "gravity" weakens as the inverse square of the distance: 1181: 1014: 921: 1845: 735:
of heat “as the point source is magnification by distances, its radiation is dilute proportional to the sin of the angle, of the increasing circumference arc from the point of origin”.
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from the source of that physical quantity. The fundamental cause for this can be understood as geometric dilution corresponding to point-source radiation into three-dimensional space.
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which is the resultant of radial inverse-square law fields with respect to one or more sources is proportional to the strength of the local sources, and hence zero outside sources.
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Newton acknowledged Wren, Hooke and Halley in this connection in the Scholium to Proposition 4 in Book 1 (in all editions): See for example the 1729 English translation of the
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In mathematical notation the inverse square law can be expressed as an intensity (I) varying as a function of distance (d) from some centre. The intensity is proportional (see
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acknowledged that Hooke, along with Wren and Halley, had separately appreciated the inverse square law in the solar system, as well as giving some credit to Bullialdus.
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of the particle velocity that is 90° out of phase with the sound pressure and does not contribute to the time-averaged energy or the intensity of the sound. The
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treatment planning, though this proportionality does not hold in practical situations unless source dimensions are much smaller than the distance. As stated in
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If the distribution of matter in each body is spherically symmetric, then the objects can be treated as point masses without approximation, as shown in the
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of a sphere increases with the square of the radius. Thus the field intensity is inversely proportional to the square of the distance from the source.
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component of the RMS particle velocity, both of which are inverse-proportional. Accordingly, the intensity follows an inverse-square behaviour:
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Williams, E.; Faller, J.; Hill, H. (1971), "New Experimental Test of Coulomb's Law: A Laboratory Upper Limit on the Photon Rest Mass",
254:{\displaystyle {\frac {{\text{intensity}}_{1}}{{\text{intensity}}_{2}}}={\frac {{\text{distance}}_{2}^{2}}{{\text{distance}}_{1}^{2}}}} 1947:
Translation of the Latin quote from Bullialdus' 'Astronomia Philolaica' … is from: O'Connor, John J. and Roberson, Edmund F. (2006)
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is similarly applicable, and can be used with any physical quantity that acts in accordance with the inverse-square relationship.
1463: 340:{\displaystyle {\text{intensity}}_{1}\times {\text{distance}}_{1}^{2}={\text{intensity}}_{2}\times {\text{distance}}_{2}^{2}} 1258:(ca. 1349), stating that it was not linearly proportional to the distance, but was unable to expose the Inverse-square law. 670:(1 AU)—an approximate threefold increase in distance results in an approximate ninefold decrease in intensity of radiation. 1958:, The MacTutor History of Mathematics Archive, School of Mathematics and Statistics, University of Saint Andrews, Scotland. 1387: 463: 950: 1120:
is zero outside the source. This can be generalized to higher dimensions. Generally, for an irrotational vector field in
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my supposition is that the attraction always is in duplicate proportion to the distance from the center reciprocall
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return, so the inverse square for both paths means that the radar will receive energy according to the inverse
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narrower spherical surface, as in the wider, thus it is as much more compressed and dense here than there.
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varies inversely with the square of the distance from the source (assuming there are no losses caused by
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Hooke remained bitter about Newton claiming the invention of this principle, even though Newton's 1686
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S represents the light source, while r represents the measured points. The lines represent the
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in three-dimensional space, the inverse-square law corresponds to the property that the
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is the radial distance from the center. The law is particularly important in diagnostic
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each approaching the other by a space proportional to the comparative mass of the other
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imminutionis eadem est, ac luminus, in ratione nempe dupla intervallorum, sed eversa.
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argued that the spreading of light from a point source obeys an inverse square law:
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in the direction of the narrow beam relative to a wide beam in all directions of an
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of the Medicean planets deduced from physical causes] (Florence, (Italy): 1666)
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discussed the inverse-square law and how it affects the intensity of light.
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In Ismaelis Bullialdi astronomiae philolaicae fundamenta inquisitio brevis
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is the attraction between objects that have mass. Newton's law states:
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the earth attracts a stone much rather than the stone seeks the earth"
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The energy or intensity decreases (divided by 4) as the distance
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Kepler is breaking away from the Aristotelian tradition that objects
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The inverse-square law generally applies when some force, energy, or
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Ad Vitellionem Paralipomena, quibus astronomiae pars optica traditur
1348:(1653) and publicized the planetary astronomy of Kepler in his book 1275:
Ad Vitellionem paralipomena, quibus astronomiae pars optica traditur
515:. The deviation of the exponent from 2 is less than one part in 10. 1719: 1702: 1550: 74: 98:
while propagating a signal, certain methods can be used such as a
1535:(1952). "An Unpublished Letter of Robert Hooke to Isaac Newton". 878: 846: 712: 431: 50: 1887:"The true theory of gravity is founded on the following axioms: 1344:(1617–1689) publicized the ideas of Bullialdus in his critique 873:
radiating from a point source decreases by 50% as the distance
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Before Galileo: The Birth of Modern Science in Medieval Europe
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given that the space outside the source is divergence free.
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emanating from the sources and fluxes. The total number of
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Hooke's letter to Newton of 6 January 1680 (Koyré 1952:332).
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fusiore, tanto ergo illie stipatior & densior quam hic.
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Theoricae Mediceorum Planetarum ex Causis Physicis Deductae
1372: 832:{\displaystyle I={\frac {P}{A}}={\frac {P}{4\pi r^{2}}}.\,} 666:); but only 1367 watts per square meter at the distance of 655: 386: 83:
energy expands during both the signal transmission and the
37: 1618:(Cambridge, England: Cambridge University Press, 2002), 1098:{\displaystyle I\ =\ pv\ \propto \ {\frac {1}{r^{2}}}.\,} 651: 579:{\displaystyle F=k_{\text{e}}{\frac {q_{1}q_{2}}{r^{2}}}} 122:) to the reciprocal of the square of the distance thus: 409:) is proportional to the square of the radius, as the 1767:"Dimensionality, symmetry and the Inverse Square Law" 1140: 1046: 982: 959: 934: 889: 780: 523: 269: 181: 128: 61:
stating that the observed "intensity" of a specified
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follows an inverse-square law, as do the effects of
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that the substance of both is of the same density."
1804:"Introduction to Non-Euclidean General Relativity" 1765:Gatzia, Dimitria Electra; Ramsier, Rex D. (2021). 1631: 1175: 1097: 1008: 966: 941: 915: 831: 578: 339: 253: 175:It can also be mathematically expressed as : 165: 2003:Sound pressure p and the inverse distance law 1/r 1755: 1680:Ryer,A. (1997) “The Light Measurement Handbook”, 650:For example, the intensity of radiation from the 263:or as the formulation of a constant quantity: 106:in order to prevent loss of energy transfer to a 2009: 1531: 1871: : 391–414 ; see especially p. 397. 770:(power per unit area) of radiation at distance 1885:, Kepler sets out his description as follows: 1860:is from: Gal, O. & Chen-Morris, R.(2005) 1669:Lighting for Film and Television – 3rd Edition 1176:{\displaystyle I\propto {\frac {1}{r^{n-1}}},} 1107: 1856:Translation of the Latin quote from Kepler's 1764: 1696: 1694: 1188: 1009:{\displaystyle v\ \propto {\frac {1}{r}}\ \,} 916:{\displaystyle p\ \propto \ {\frac {1}{r}}\,} 711:The fractional reduction in electromagnetic 1967:(Gal & Chen-Morris, 2005), pp. 391–392. 1918:to be in their natural place, that a stone 451:while calculating the gravitational force. 1691: 1501:The History of the Royal Society of London 1980:… (London, England: John Martyn, 1667), 1718: 1094: 1005: 963: 938: 912: 828: 589:Light and other electromagnetic radiation 162: 1525: 1260: 31: 1273:In proposition 9 of Book 1 in his book 1193:The inverse-square law, fundamental in 609:or other linear waves radiating from a 14: 2010: 1700: 1503:, … (London, England: 1756), vol. 2, 953:with the instantaneous sound pressure 925:The same is true for the component of 1256:Summa logicæ et philosophiæ naturalis 359:Newton's law of universal gravitation 1998:Damping of sound level with distance 1355:In 1663–1664, the English scientist 1317: 1283: 658:per square meter at the distance of 1703:"Non-Euclidean Newtonian Cosmology" 24: 628:per unit area in the direction of 389:is evenly radiated outward from a 25: 2034: 1991: 1935:… (Paris, France: Piget, 1645), 1616:The Cambridge Companion to Newton 1490:Tycho Brahe to Newton", CUP 1989. 1404:William Thomson, 1st Baron Kelvin 1388:Kepler's laws of planetary motion 853: 499: 1457: This article incorporates 1452: 1340:In England, the Anglican bishop 1227:to the dimensionality of space. 620:More generally, the irradiance, 462:. But Bullialdus did not accept 454:As the law of gravitation, this 380: 1970: 1961: 1941: 1925: 1874: 1850: 1834: 1821: 1796: 1674: 1470:General Services Administration 1661: 1625: 1607: 1590: 1581: 1510: 1493: 1483: 464:Kepler's second and third laws 426: 421: 13: 1: 1707:Classical and Quantum Gravity 1507:; see especially pages 70–72. 1446: 1409:Power-aware routing protocols 7: 1858:Ad Vitellionem paralipomena 1366: 1311:..., the French astronomer 1108:Field theory interpretation 845:is doubled; if measured in 617:(in the same time period). 10: 2039: 1809:. MIT OpenCourseWare. 2018 1656:10.1103/PhysRevLett.26.721 1516:Giovanni Alfonso Borelli, 1238: 1189:Non-Euclidean implications 1132: − 1) power law 738: 503: 113: 1114:irrotational vector field 458:was suggested in 1645 by 1954:30 November 2016 at the 1737:10.1088/1361-6382/ab8437 1701:Barrow, John D. (2020). 1321: 1287: 1199:non-Euclidean geometries 1197:spaces, also applies to 877:is doubled; measured in 476:Giovanni Alfonso Borelli 466:, nor did he appreciate 387:other conserved quantity 1910:Notice that in saying " 1635:Physical Review Letters 1441:Principle of similitude 1416:Inverse proportionality 1277:(1604), the astronomer 1034:sound pressure and the 416:Gauss's law for gravity 395:three-dimensional space 94:To prevent dilution of 1783:10.1098/rsnr.2019.0044 1465:Federal Standard 1037C 1459:public domain material 1421:Multiplicative inverse 1329: 1295: 1270: 1177: 1099: 1030:is the product of the 1010: 968: 943: 917: 833: 580: 441: 341: 255: 167: 67:inversely proportional 46: 2018:Philosophy of physics 1933:Astronomia Philolaica 1922:to be with the earth. 1359:was writing his book 1350:Astronomia geometrica 1309:Astronomia Philolaica 1307:In 1645, in his book 1264: 1178: 1100: 1011: 969: 944: 918: 834: 581: 436: 342: 256: 168: 35: 1667:Millerson,G. (1991) 1246:of the 14th-century 1138: 1044: 1024:quadrature component 980: 957: 932: 887: 778: 521: 267: 179: 126: 1931:Ismail Bullialdus, 1743:on 25 February 2020 1729:2020CQGra..37l5007B 1648:1971PhRvL..26..721W 1476:on 22 January 2022. 967:{\displaystyle p\,} 942:{\displaystyle v\,} 675:isotropic radiators 336: 301: 248: 231: 1865:History of Science 1398:Telecommunications 1271: 1265:German astronomer 1252:mean speed theorem 1248:Oxford Calculators 1233:special relativity 1211:general relativity 1173: 1095: 1006: 964: 939: 913: 829: 749:isotropic radiator 681:, headlights, and 679:parabolic antennas 624:the intensity (or 576: 468:Christiaan Huygens 414:the point source. 337: 320: 285: 251: 232: 215: 163: 55:inverse-square law 47: 18:Inverse square law 2023:Scientific method 1949:"Ismael Boulliau" 1840:Johannes Kepler, 1771:Notes and Records 1338: 1337: 1313:Ismaël Bullialdus 1304: 1303: 1168: 1089: 1073: 1067: 1058: 1052: 1004: 1000: 988: 927:particle velocity 910: 901: 895: 823: 795: 691:isotropic antenna 574: 537: 460:Ismaël Bullialdus 411:emitted radiation 405:(which is 4π 324: 309: 289: 274: 249: 236: 219: 208: 200: 188: 160: 152: 142: 136: 132: 63:physical quantity 16:(Redirected from 2030: 1985: 1974: 1968: 1965: 1959: 1945: 1939: 1929: 1923: 1878: 1872: 1854: 1848: 1838: 1832: 1825: 1819: 1818: 1816: 1814: 1808: 1800: 1794: 1793: 1791: 1789: 1762: 1753: 1752: 1750: 1748: 1739:. 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Archived from 1456: 1455: 1400:, particularly: 1318: 1284: 1203:hyperbolic space 1182: 1180: 1179: 1174: 1169: 1167: 1166: 1148: 1104: 1102: 1101: 1096: 1090: 1088: 1087: 1075: 1071: 1065: 1056: 1050: 1015: 1013: 1012: 1007: 1002: 1001: 993: 986: 973: 971: 970: 965: 948: 946: 945: 940: 922: 920: 919: 914: 911: 903: 899: 893: 838: 836: 835: 830: 824: 822: 821: 820: 801: 796: 788: 706:square root of 2 585: 583: 582: 577: 575: 573: 572: 563: 562: 561: 552: 551: 541: 539: 538: 535: 346: 344: 343: 338: 335: 330: 325: 322: 316: 315: 310: 307: 300: 295: 290: 287: 281: 280: 275: 272: 260: 258: 257: 252: 250: 247: 242: 237: 234: 230: 225: 220: 217: 214: 209: 207: 206: 201: 198: 195: 194: 189: 186: 183: 172: 170: 169: 164: 161: 159: 158: 153: 150: 144: 140: 134: 133: 130: 21: 2038: 2037: 2033: 2032: 2031: 2029: 2028: 2027: 2008: 2007: 1994: 1989: 1988: 1975: 1971: 1966: 1962: 1956:Wayback Machine 1946: 1942: 1930: 1926: 1883:Astronomia Nova 1879: 1875: 1855: 1851: 1839: 1835: 1826: 1822: 1812: 1810: 1806: 1802: 1801: 1797: 1787: 1785: 1763: 1756: 1746: 1744: 1699: 1692: 1679: 1675: 1666: 1662: 1642:(12): 721–724, 1630: 1626: 1612: 1608: 1595: 1591: 1586: 1582: 1530: 1526: 1515: 1511: 1498: 1494: 1488: 1484: 1462: 1453: 1451: 1449: 1436:Square–cube law 1378:Antenna (radio) 1369: 1334: 1326: 1306: 1300: 1292: 1279:Johannes Kepler 1267:Johannes Kepler 1241: 1191: 1156: 1152: 1147: 1139: 1136: 1135: 1126:Euclidean space 1110: 1083: 1079: 1074: 1045: 1042: 1041: 1028:sound intensity 992: 981: 978: 977: 958: 955: 954: 933: 930: 929: 902: 888: 885: 884: 856: 816: 812: 805: 800: 787: 779: 776: 775: 741: 591: 568: 564: 557: 553: 547: 543: 542: 540: 534: 530: 522: 519: 518: 508: 502: 429: 424: 383: 331: 326: 321: 311: 306: 305: 296: 291: 286: 276: 271: 270: 268: 265: 264: 243: 238: 233: 226: 221: 216: 213: 202: 197: 196: 190: 185: 184: 182: 180: 177: 176: 154: 149: 148: 143: 129: 127: 124: 123: 116: 28: 23: 22: 15: 12: 11: 5: 2036: 2026: 2025: 2020: 2006: 2005: 2000: 1993: 1992:External links 1990: 1987: 1986: 1976:Robert Hooke, 1969: 1960: 1940: 1924: 1873: 1849: 1833: 1820: 1795: 1777:(2): 333–347. 1754: 1713:(12): 125007. 1690: 1673: 1660: 1624: 1606: 1589: 1580: 1551:10.1086/348155 1545:(4): 312–337. 1524: 1509: 1499:Thomas Birch, 1492: 1481: 1480: 1448: 1445: 1444: 1443: 1438: 1433: 1428: 1426:Distance decay 1423: 1418: 1413: 1412: 1411: 1406: 1395: 1393:Kepler problem 1390: 1385: 1380: 1375: 1368: 1365: 1336: 1335: 1327: 1302: 1301: 1293: 1244:John Dumbleton 1240: 1237: 1221:John D. Barrow 1190: 1187: 1172: 1165: 1162: 1159: 1155: 1151: 1146: 1143: 1109: 1106: 1093: 1086: 1082: 1078: 1070: 1064: 1061: 1055: 1049: 999: 996: 991: 985: 962: 937: 909: 906: 898: 892: 864:sound pressure 855: 854:Sound in a gas 852: 827: 819: 815: 811: 808: 804: 799: 794: 791: 786: 783: 759: = 4 740: 737: 733:Fourier theory 702:stage lighting 590: 587: 571: 567: 560: 556: 550: 546: 533: 529: 526: 506:Electrostatics 504:Main article: 501: 500:Electrostatics 498: 449:center of mass 428: 425: 423: 420: 382: 379: 334: 329: 319: 314: 304: 299: 294: 284: 279: 246: 241: 229: 224: 212: 205: 193: 157: 147: 139: 115: 112: 91:of the range. 59:scientific law 26: 9: 6: 4: 3: 2: 2035: 2024: 2021: 2019: 2016: 2015: 2013: 2004: 2001: 1999: 1996: 1995: 1983: 1979: 1973: 1964: 1957: 1953: 1950: 1944: 1938: 1934: 1928: 1921: 1917: 1913: 1909: 1905: 1903: 1896: 1895: 1891: 1888: 1884: 1877: 1870: 1866: 1863: 1859: 1853: 1847: 1843: 1837: 1830: 1827:John Freely, 1824: 1805: 1799: 1784: 1780: 1776: 1772: 1768: 1761: 1759: 1742: 1738: 1734: 1730: 1726: 1721: 1716: 1712: 1708: 1704: 1697: 1695: 1687: 1686:0-9658356-9-3 1683: 1677: 1670: 1664: 1657: 1653: 1649: 1645: 1641: 1637: 1636: 1628: 1621: 1617: 1610: 1603: 1599: 1593: 1584: 1576: 1572: 1568: 1564: 1560: 1556: 1552: 1548: 1544: 1540: 1539: 1534: 1528: 1521: 1520: 1513: 1506: 1502: 1496: 1486: 1482: 1479: 1475: 1471: 1467: 1466: 1460: 1442: 1439: 1437: 1434: 1432: 1431:Fermi paradox 1429: 1427: 1424: 1422: 1419: 1417: 1414: 1410: 1407: 1405: 1402: 1401: 1399: 1396: 1394: 1391: 1389: 1386: 1384: 1381: 1379: 1376: 1374: 1371: 1370: 1364: 1362: 1358: 1353: 1351: 1347: 1343: 1333: 1328: 1325: 1320: 1319: 1316: 1314: 1310: 1299: 1294: 1291: 1286: 1285: 1282: 1280: 1276: 1268: 1263: 1259: 1257: 1253: 1249: 1245: 1236: 1234: 1228: 1224: 1222: 1218: 1216: 1215:string theory 1212: 1208: 1204: 1200: 1196: 1186: 1183: 1170: 1163: 1160: 1157: 1153: 1149: 1144: 1141: 1133: 1131: 1127: 1124:-dimensional 1123: 1119: 1115: 1105: 1091: 1084: 1080: 1076: 1068: 1062: 1059: 1053: 1047: 1039: 1037: 1033: 1029: 1025: 1021: 1016: 997: 994: 989: 983: 975: 960: 952: 935: 928: 923: 907: 904: 896: 890: 882: 880: 876: 872: 869: 865: 861: 851: 848: 844: 839: 825: 817: 813: 809: 806: 802: 797: 792: 789: 784: 781: 773: 769: 766: 762: 758: 754: 750: 746: 736: 734: 730: 726: 722: 718: 714: 709: 707: 703: 699: 694: 692: 688: 684: 680: 676: 671: 669: 665: 661: 657: 653: 648: 646: 642: 638: 635: 631: 627: 623: 618: 616: 612: 608: 604: 600: 596: 586: 569: 565: 558: 554: 548: 544: 531: 527: 524: 516: 514: 513:Coulomb's law 507: 497: 495: 494: 488: 486: 482: 477: 473: 469: 465: 461: 457: 452: 450: 446: 445:shell theorem 440: 435: 433: 419: 417: 412: 408: 404: 400: 397:. Since the 396: 392: 388: 381:Justification 378: 376: 372: 368: 364: 360: 356: 352: 347: 332: 327: 317: 312: 302: 297: 292: 282: 277: 261: 244: 239: 227: 222: 210: 203: 191: 173: 155: 145: 137: 121: 111: 109: 105: 101: 97: 92: 90: 86: 82: 78: 76: 72: 68: 64: 60: 56: 52: 43: 39: 34: 30: 19: 1978:Micrographia 1977: 1972: 1963: 1943: 1932: 1927: 1919: 1915: 1911: 1906: 1901: 1898: 1893: 1892: 1889: 1886: 1882: 1876: 1868: 1864: 1857: 1852: 1841: 1836: 1828: 1823: 1811:. Retrieved 1798: 1786:. Retrieved 1774: 1770: 1745:. Retrieved 1741:the original 1710: 1706: 1676: 1668: 1663: 1639: 1633: 1627: 1615: 1609: 1597: 1592: 1583: 1542: 1536: 1527: 1518: 1512: 1500: 1495: 1485: 1474:the original 1464: 1450: 1361:Micrographia 1360: 1357:Robert Hooke 1354: 1349: 1345: 1339: 1330: 1322: 1308: 1305: 1296: 1288: 1274: 1272: 1255: 1242: 1229: 1225: 1219: 1201:, including 1192: 1184: 1134: 1129: 1121: 1111: 1040: 1035: 1017: 976: 924: 883: 874: 857: 842: 840: 771: 767: 760: 756: 752: 744: 742: 729:radiotherapy 720: 716: 710: 695: 687:antenna gain 672: 649: 621: 619: 611:point source 592: 517: 509: 491: 489: 484: 481:Isaac Newton 472:Robert Hooke 453: 442: 437: 430: 406: 399:surface area 391:point source 384: 355:vector field 348: 262: 174: 117: 93: 89:fourth power 79: 54: 48: 29: 27:Physical law 1505:pages 68–73 1383:Gauss's law 725:radiography 698:photography 630:propagation 599:illuminance 432:Gravitation 427:Gravitation 422:Occurrences 377:phenomena. 2012:Categories 1720:2002.10155 1602:at page 66 1447:References 1118:divergence 1020:near field 645:scattering 641:absorption 603:irradiance 351:divergence 42:flux lines 1982:page 227: 1598:Principia 1342:Seth Ward 1207:cosmology 1195:Euclidean 1161:− 1145:∝ 1069:∝ 990:∝ 897:∝ 871:wavefront 868:spherical 860:acoustics 810:π 765:intensity 637:wavefront 634:spherical 595:intensity 493:Principia 375:radiation 318:× 308:intensity 283:× 273:intensity 199:intensity 187:intensity 138:∝ 131:intensity 104:dimension 100:waveguide 85:reflected 1952:Archived 1937:page 23. 1846:page 10. 1620:page 204 1575:41626961 1567:13010921 1367:See also 1352:(1656). 1036:in-phase 951:in-phase 949:that is 677:such as 673:For non- 654:is 9126 632:), of a 363:electric 323:distance 288:distance 235:distance 218:distance 151:distance 75:distance 1813:30 July 1788:30 July 1747:30 July 1725:Bibcode 1644:Bibcode 1239:History 1112:For an 1018:In the 739:Example 713:fluence 662:(0.387 660:Mercury 114:Formula 73:of the 69:to the 57:is any 51:science 1831:(2012) 1684:  1573:  1565:  1559:227384 1557:  1213:, and 1072:  1066:  1057:  1051:  1003:  987:  900:  894:  862:, the 763:, the 719:where 683:lasers 615:energy 403:sphere 373:, and 141:  135:  108:bullet 96:energy 71:square 1920:seeks 1807:(PDF) 1715:arXiv 1571:S2CID 1555:JSTOR 1461:from 1022:is a 866:of a 668:Earth 656:watts 626:power 622:i.e., 607:light 605:) of 439:them. 401:of a 371:sound 367:light 353:of a 81:Radar 53:, an 1916:seek 1897:... 1815:2023 1790:2023 1749:2023 1688:p.26 1682:ISBN 1671:p.27 1563:PMID 1538:Isis 1373:Flux 743:Let 727:and 700:and 597:(or 593:The 474:and 349:The 38:flux 1779:doi 1733:doi 1652:doi 1547:doi 1032:RMS 858:In 774:is 755:is 696:In 652:Sun 647:). 643:or 601:or 483:: 456:law 393:in 65:is 49:In 2014:: 1984:"" 1869:43 1867:, 1775:75 1773:. 1769:. 1757:^ 1731:. 1723:. 1711:37 1709:. 1705:. 1693:^ 1650:, 1640:26 1638:, 1600:, 1569:. 1561:. 1553:. 1543:43 1541:. 1468:. 1217:. 1209:, 974:: 879:dB 847:dB 761:πr 693:. 664:AU 487:. 369:, 365:, 110:. 1904:. 1817:. 1792:. 1781:: 1751:. 1735:: 1727:: 1717:: 1654:: 1646:: 1622:. 1604:. 1577:. 1549:: 1171:, 1164:1 1158:n 1154:r 1150:1 1142:I 1130:n 1122:n 1092:. 1085:2 1081:r 1077:1 1063:v 1060:p 1054:= 1048:I 998:r 995:1 984:v 961:p 936:v 908:r 905:1 891:p 875:r 843:r 826:. 818:2 814:r 807:4 803:P 798:= 793:A 790:P 785:= 782:I 772:r 768:I 757:A 753:r 745:P 721:r 717:r 570:2 566:r 559:2 555:q 549:1 545:q 536:e 532:k 528:= 525:F 407:r 333:2 328:2 313:2 303:= 298:2 293:1 278:1 245:2 240:1 228:2 223:2 211:= 204:2 192:1 156:2 146:1 120:∝ 20:)

Index

Inverse square law

flux
flux lines
science
scientific law
physical quantity
inversely proportional
square
distance
Radar
reflected
fourth power
energy
waveguide
dimension
bullet

divergence
vector field
Newton's law of universal gravitation
electric
light
sound
radiation
other conserved quantity
point source
three-dimensional space
surface area
sphere

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