The Tanzanian student who discovered this phenomenon gave a lot of scientists a headache.
But now here is the explaination.
The effect is named after Tanzanian Erasto Mpemba. He first encountered the phenomenon in 1963 in Form 3 of Magamba Secondary School, Tanganyika when freezing ice cream mix that was hot in cookery classes and noticing that it froze before the cold mix. After passing his O-level examinations, he became a student at Mkwawa Secondary (formerly High) School, Iringa, Tanzania. The headmaster invited Dr. Denis G. Osborne from the University College in Dar Es Salaam to give a lecture on physics. After the lecture, Erasto Mpemba asked him the question "If you take two similar containers with equal volumes of water, one at 35 °C (95 °F) and the other at 100 °C (212 °F), and put them into a freezer, the one that started at 100 °C (212 °F) freezes first. Why?" only to be ridiculed by his classmates and teacher. After initial consternation, Dr. Osborne experimented on the issue back at his workplace and confirmed Mpemba's finding. They published the results together in 1969.
huyu aliyeandika habari hii ni bora angetumia kiswahili ili ieleweke vizuri WHEN FREEZING ICE CREAM MIX THAT WAS HOT IN COOKERY CLASSES AND NOTICING THAT IT FROZE BEFORE THE COLD MIX kiingereza chake kigumu jamani naomba msaada.
ReplyDeleteMaana ya ''WHEN FREEZING ICE CREAM MIX THAT WAS HOT IN COOKERY CLASSES AND NOTICING THAT IT FROZE BEFORE THE COLD MIX'' kwa Kiswahili ni: Unapochukua mchanganyiko wa ashikirimu iliyo bado moto na kuiweka moja kwa moja ktk friza ya friji ni kuwa huganda haraka zaidi ya mchanganyiko wa ashikirimu iliyoachwa kupoa kwanza halafu ukaiweka ndani ya friza ya friji.
ReplyDeleteKwa kifupi hata maji ya uvuguvugu huganda haraka ndani ya freza ya friji kuliko maji yaliyopoa (room temperature).
Vivyo hivyo ktk nchizenye hali ya ubaridi kaskazi ya dunia mfano Ulaya na Amerika ya Kaskazini n.k kuyamwaga maji moto toka katika flaski ya chai, maji moto hayo hugeuka kuwa snow dust/flake lakini ukitumia maji baridi hupati hali hiyo ya snow dusk/flakes.
Mdau
Kitulo Nyanda za Juu Kusini Tz kwenye Snow.
Ndugu yangu hapo juu. Al-awal naomba usifikirie kuwa naipigia debe lugha ya kidhungu. Wengi wetu bado tuna kero kuwa hii ni lugha ya wakoloni watu walio tutesa na kutuibia kwa muda mrefu. lakini siku hizi hapa duniani lugha ya kiingereza ina faida kubwa sana. Hivyo nakuomba usikae wangojea tafsiri,jifunze lugha.Tumia mtandao kujielimisha,Google:Teach yourself English
ReplyDeleteWakatabahu
picha yenyewe haionekani,fundi mitambo tafadhali rekebisha tuna shauku ya kuiona hiyo picha
ReplyDeleteSina mengi ila ninachojiuliza ni kwa nini katika elimu yangu ya Tanzania kutokea chekechea hadi Form 4 sijawahi kufundushwa kuhusu MPEMBA EFFECT....ukizingatia nilikuwa kwenye mchipuo wa Tanzania.
ReplyDeleteHivi kwa nini watanzania hatujitambui na kujithamini. Yaani nimefundishwa kuhusu akina Newton, Pascal....lakini Mpemba kafanya makubwa lakini sijamsikia. Hebu wamthamini Mpemba kwa kumweka kwenye vitabu vya Tanzania ili awatie sisi wote moyo kwamba tulivumbua zamani na bado tunaweza kuvumbua mengi makubwa. Nimemaliza kwa leo.