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seminarski rad. metode i značaj određivanja gravitacione konstante “ big G ”. tri fundamentalne univerzalne konstante u prirodi. brzina svetlosti C plankova konstanta h gravitaciona konstanta G. Gundlach said :.
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seminarski rad metode i značaj određivanja gravitacione konstante “big G”
tri fundamentalne univerzalne konstante u prirodi • brzina svetlosti C • plankova konstanta h • gravitaciona konstanta G
Gundlach said: "That is a huge embarrassment for modern physics, where we think we know everything so well and other constants are defined to many, many digits.“ “Ovo je velika neprijatnostza modernu fiziku, gde mislimo da znamo sve tako dobro i gde su druge konstante određene sa mnogo, mnogo decimala.”
henry cavendish1798G=6.75x10-11Nm2/kg2The torsion balance experiment of Henry Cavendish who in 1797 was the first to experimentally measure the gravitational constant G.
neki od razloga za pojavu sistematskih grešaka • promenljivost torzionog momenta • pomeranje podloge (podrhtavanja zemlje) • uticaj masa tela iz okruženja • nehomogenost masa tela koja su sastavni deo eksperimenta • gradijent gravitacionog polja • gradijent temperature • magnetni i električni uticaj
G gravitaciona konstanta • L rastojanje između tela malih masa • q ugao otklona • k torziona konstanta
Schematic view of the mass arrangement. The test masses are alternately connected to the balance by means of the “mass exchanger” and their weight difference is determined. The field masses are moved between the two positions I and II. The forces on the upper test mass due to the Earth, the field masses and tidal forces are plotted for the two field-mass positions on the left and right of the figure.
The orbiting Lageos satellite monitors its position relative to the Earth using reflected laser light. From the measured gravitational force between satellite and our planet, and independently measuring G, one can calculate the mass of the Earth.
The apparatus used by the research group at the University of Washington, Seattle, to measure G to record high precision. The device, about two feet across, measures the attractiveness between a hanging plate (hidden inside the cylinder) and several spheres which rotate about the cylinder.
tačnost sata je uslovljena konstantnom vrednošću perioda oscilovanja torzionog klatna za dati momenat inercije