Ikilo kimwe gipima angahe? Abahanga mu bya siyansi bamaze imyaka amagana basesengura iki kibazo gisa n'aho cyoroshye.
Mu 1795, Ubufaransa bwashyizeho itegeko ryavugaga ko "garama" ari "uburemere bw'amazi mu gice cy'amazi gifite ingano ingana na kimwe cya ijana cya metero ku bushyuhe iyo urubura rushongeshejwe (ni ukuvuga 0°C)." Mu 1799, abahanga mu bya siyansi bavumbuye ko ingano y'amazi ari yo ihamye cyane iyo ubucucike bw'amazi buri hejuru kuri 4°C, bityo ibisobanuro bya kilo byahindutse "uburemere bwa desimetero kibe imwe y'amazi meza kuri 4°C". Ibi byatanze kilometero y'umwimerere ya platine, kilometero isobanurwa ko ingana n'uburemere bwayo, byitwa kilometero y'ububiko.
Iki kilo cy’ububiko cyakoreshejwe nk'icyitegererezo mu myaka 90. Mu 1889, Inama Mpuzamahanga ya Mbere ku byerekeye Metrologiya yemeje kopi ya platine-iridium alloy iri hafi cyane ya kilo cy’ububiko nk'ikilo mpuzamahanga cy’umwimerere. Uburemere bwa "kilo" bugenwa na silindiri ya platine-iridium (90% platine, 10% iridium), ifite uburebure n'umurambararo wa mm 39, kandi ubu ibikwa mu cyumba cyo munsi y’ubutaka mu nkengero za Paris.
Ikilo cy'umwimerere mpuzamahanga
Kuva mu gihe cy'Umucyo, umuryango w’abakora ubushakashatsi wiyemeje gushyiraho uburyo bwo gupima ku isi yose. Nubwo ari uburyo bushoboka bwo gukoresha ikintu gifatika nk'igipimo, kubera ko ikintu gifatika cyangirika byoroshye bitewe n'ibintu byakozwe n'abantu cyangwa ibidukikije, guhagarara neza bizagira ingaruka, kandi umuryango w’abakora ubushakashatsi wahoraga wifuza kureka ubu buryo vuba bishoboka.
Nyuma yuko ikiro gikoresheje ibisobanuro mpuzamahanga bya kilogarama y’umwimerere, hari ikibazo abahanga mu by’imiterere y’ikirere bahangayikishijwe cyane na cyo: ese iki gisobanuro gihamye gite? Ese kizagenda gihinduka uko igihe kigenda gihita?
Byagombye kuvugwa ko iki kibazo cyabajijwe mu ntangiriro y'igisobanuro cy'ibiro by'uburemere. Urugero, ubwo ikiro cyasobanurwaga mu 1889, Ikigo Mpuzamahanga gishinzwe Uburemere n'Ibipimo cyakoze ibiro 7 bya platine-iridium alloy kilogram, kimwe muri byo kikaba ari ikiro cy'umwimerere cyakoreshejwe mu gusobanura ibiro by'uburemere, naho ibindi biremere 6 bikozwe mu bikoresho bimwe n'uburyo bumwe bikoreshwa nk'ibipimo bya kabiri kugira ngo harebwe niba hari ukugendana kw'ibintu uko igihe kigenda gihita.
Muri icyo gihe, hamwe n’iterambere ry’ikoranabuhanga rigezweho, dukeneye kandi ibipimo bihamye kandi by’ukuri. Kubwibyo, hatanzwe gahunda yo kuvugurura urwego mpuzamahanga rw’ibanze hamwe n’ibipimo bifatika. Gukoresha ibipimo bihoraho mu gusobanura ibipimo bivuze ko ibi bisobanuro bizahura n’ibyo abantu bo mu gihe kizaza bavumbuye mu bya siyansi bakeneye.
Dukurikije amakuru yemewe y’Ikigo Mpuzamahanga gishinzwe Uburemere n’Ibipimo, mu myaka 100 kuva mu 1889 kugeza mu 2014, imiterere y’ibindi bilo by’umwimerere n’ibilo mpuzamahanga by’umwimerere byahindutseho mikorogarama zigera kuri 50. Ibi bigaragaza ko hari ikibazo ku buryo imiterere y’ibipimo by’ubwiza ihagaze. Nubwo impinduka ya mikorogarama 50 isa n’aho ari nto, bigira ingaruka zikomeye ku nganda zimwe na zimwe zo mu rwego rwo hejuru.
Iyo ibipimo by'ibanze bya fiziki bikoreshejwe mu gusimbuza ikigero cya kilogarama, ubwiza bw'igice cy'uburemere ntabwo buzahinduka bitewe n'umwanya n'igihe. Kubwibyo, mu 2005, Komite Mpuzamahanga ishinzwe Ibipimo n'Ibipimo yateguye urwego rwo gukoresha ibipimo by'ibanze bya fiziki mu gusobanura bimwe mu bice by'ibanze bya Sisitemu Mpuzamahanga y'Ibipimo. Birasabwa ko ibipimo bya Planck bikoreshwa mu gusobanura ikigero cya kilogarama, kandi laboratwari zo ku rwego rw'igihugu zibifitiye ubushobozi zirashishikarizwa gukora ubushakashatsi bwa siyansi bujyanye nabyo.
Kubwibyo, mu nama mpuzamahanga ya 2018 ku bijyanye n'ibipimo, abahanga mu bya siyansi batoye ko ikiro cy’icyitegererezo mpuzamahanga cyakuweho ku mugaragaro, kandi bahindura igipimo cya Planck (ikimenyetso h) nk'igipimo gishya cyo kongera gusobanura "kg".
Igihe cyo kohereza ubutumwa: Werurwe-05-2021