H varyitiki (i alliws vareia) maza mb enos swmatos, einai auti pou mporei na vrethei me ti metrisi tis dynamis poy askeitai sto swma apo ena allo, opws px ti Gh. O ypologismos ginetai apo ti sxesi F=GMmb/R^2
opou M h vareia Maza tis Ghs, G h stathera tis pagosmias elxis kai R i apostasi apo to kentro tis gis. H adranis maza ma prokyptei apo to 2o nomo tou newton, ma*(du/dt)=F
Me peiramata akriveias, exoume epalitheusei oti ma=mb. H arxi auti onomazetai kai arxi tis isodynamias.
H F=m*a einai o 2os nomos tou Newton. H F=GMm/r^2 einai o nomos gia ti varytita.
Gia ena swma me adraneiaki maza ma(1) kai barytiki mb(1) poy peftei plision tis epifaneias tis gis, isxuei
GMmb(1)/r^2=ma(1)*a(1)
opou a einai h epitaxynsi.
H idia sxesi isxyei kai gia ena swma (2):
GMmb(2)/r^2=ma(2)*a(2)
Diairwntas tis dyo sxeseis, kai epeidi exei parattirithei oti ola ta swmata peftoun sti Gh me tin idia epitaxynsi, a(1)=a(2) pairnoyme
ma(1)/mb(1)=ma(2)/mb(2)
Diladi ta peiramatika apotelesmata apaitoun tin analogikotita tis vareias kai tis adranous mazas. Me peiramata polu megalis akribeias, opws eipa prin, exei diapistwthei oti ma=mb
Basika to erwtima den exei na kanei me mathimatikous typous (aytoi erxontai argotera an labei kaneis ypopsin thn arxi tis isodynamias tou neutwna) etsi h maza m orizetai to metro ths adraneias ths ylhs kai h barytikh maza m' ws h phgh tou baritikou pedioy. Etsi h arxh ths isodynamias tou neytwna perigrafetai apo th sxesi m=sqrt(G)m'
