Kedu otu kilogram na-atụ? Ndị ọkà mmụta sayensị enyochala nsogbu a nke yiri ka ọ dị mfe kemgbe ọtụtụ narị afọ.
N'afọ 1795, France wepụtara iwu nke kwuru na "gram" dị ka "ịdị arọ nke mmiri dị n'otu kube nke olu ya hà nhata otu narị mita na okpomọkụ mgbe ice gbazere (ya bụ, 0 ° C). N'afọ 1799, ndị ọkà mmụta sayensị chọpụtara na oke mmiri bụ ihe kacha kwụsie ike mgbe njupụta nke mmiri dị elu na 4 Celsius C, ya mere nkọwa nke kilogram agbanweela na "oke nke 1 cubic decimeter nke mmiri dị ọcha na 4 ° C". Nke a na-emepụta kilogram mbụ platinum dị ọcha, a na-akọwa kilogram ahụ ka nha nha ya, nke a na-akpọ Archive kilogram.
A na-eji kilogram nchekwa nchekwa a mee ihe dị ka ihe nrịbama kemgbe afọ iri itoolu. N'afọ 1889, Nzukọ Mba Nile nke Mbụ na Metrology kwadoro ihe oyiri platinum-iridium alloy kacha nso na kilogram ebe nchekwa dị ka kilogram mbụ nke mba ụwa. A na-akọwa ịdị arọ nke "kilogram" site na platinum-iridium alloy (90% platinum, 10% iridium) cylinder, nke dị ihe dịka 39 mm n'ịdị elu na dayameta, ma na-echekwa ugbu a na okpuru ulo na mpụga Paris.
Kilogram mbụ nke mba ụwa
Site na Age of Enlightenment, ndị obodo na-eme nyocha etinyela aka n'ịhazi usoro nyocha zuru ụwa ọnụ. Ọ bụ ezie na ọ bụ ụzọ dị mma isi jiri ihe anụ ahụ dị ka akara nha nha, n'ihi na ihe anụ ahụ na-eme ngwa ngwa site na ihe mmadụ mere ma ọ bụ gburugburu ebe obibi, nkwụsi ike ga-emetụta, na ndị na-ahụ maka nha na-achọkarị ịhapụ usoro a ozugbo enwere ike.
Mgbe kilogram ahụ nakweere nkọwa nke kilogram mbụ nke mba ụwa, enwere ajụjụ nke ndị ọkà mmụta metrologists na-echegbu onwe ya: kedu ka nkọwa a si kwụsie ike? Ọ ga-adị ogologo oge?
Ekwesịrị ịsị na a jụrụ ajụjụ a na mmalite nke nkọwa nke otu kilogram kilogram. Dịka ọmụmaatụ, mgbe a kọwara kilogram ahụ na 1889, International Bureau of Weights and Measures wepụtara 7 platinum-iridium alloy kilogram weights, otu n'ime ha bụ International A na-eji kilogram mbụ akọwa ihe dị arọ nke kilogram, na 6 ndị ọzọ na-eji otu ihe na otu usoro ahụ mee ihe dị ka akara nke abụọ iji chọpụta ma ọ dị mkpagharị oge n'etiti ibe ya.
N'otu oge ahụ, site na mmepe nke nkà na ụzụ dị elu, anyị chọkwara ihe ndị ọzọ kwụsiri ike na nke ziri ezi. Ya mere, a tụpụtara atụmatụ iji kọwapụta otu isi nke mba ụwa na nkwụsi ike anụ ahụ. Iji ihe na-adịgide adịgide kọwaa nkeji nha pụtara na nkọwa ndị a ga-egbo mkpa ọgbọ na-esote nchọpụta sayensị.
Dabere na data gọọmentị nke International Bureau of Weights and Measures, n'ime 100 afọ site na 1889 ruo 2014, ịdị mma nke kilogram mbụ ndị ọzọ na kilogram mbụ nke mba ụwa gbanwere site na ihe dị ka microgram 50. Nke a na-egosi na enwere nsogbu na nkwụsi ike nke benchmark anụ ahụ nke ịdị mma. Ọ bụ ezie na mgbanwe nke 50 micrograms na-ada ụda obere, ọ na-enwe mmetụta dị ukwuu na ụfọdụ ụlọ ọrụ dị elu.
Ọ bụrụ na a na-eji ihe ndị bụ isi nke anụ ahụ mee ihe iji dochie anya akara anụ ahụ nke kilogram, nkwụsi ike nke akụkụ ahụ agaghị emetụta ohere na oge. Ya mere, na 2005, International Committee for Weights and Measures depụtara a framework maka ojiji nke isi nkịtị constants kọwaa ụfọdụ isi nkeji nke International System of Units. A na-atụ aro ka a na-eji Planck mgbe niile kọwaa otu kilogram nke oke, yana a na-agbakwa ụlọ nyocha ọkwa mba ruru eru ịrụ ọrụ nyocha sayensị metụtara ya.
Ya mere, na 2018 International Conference on Metrology, ndị ọkà mmụta sayensị tozuru oke ka ha wepụ kilogram nke mba ụwa, ma gbanwee Planck nọgidere (akara h) dị ka ọkọlọtọ ọhụrụ iji kọwaa "kg".
Oge nzipu: Mar-05-2021