Ugunduzi wa Erasto Mpemba, (Maji ya moto kuganda haraka kuliko ya baridi) 'The Mpemba Effect' kwanini hatukufundishwa mashuleni?

[Mzee Dogo]

 

[New City]

Hii ni nadharia (theory) tu ,haijathibitishwa (proven) na pia sio ugunduzi yaani Invention kwa hiyo sielewi comment zako zinalenga nini hasa wakati hata jina la hiyo observation wameipa la huyo jamaa.

Yeah it's just a merely theory,but it takes a courage of one to develop a such theory.You and I have dared to develop nothing ,and after all his mere observation has been appreciated and published in physics journals ,
Tukubali tu ,jamaa alikuwa na kitu special kutuzidi,hizi roho za kwanini hazitupeleki popote.

 

[Sisyphus]

Kwa kweli ugunduzi huu wa mpemba kama ungetiliwa mkazo, najua angekuwa mbali sana na katika vitabu vya wagunduzi basi angekuwa mmoja wao..tena wagunduzi nguli wa fizikia

ushatiliwa mkazo sana mpaka majibu yakapatikana

 

[Ng'wanamangilingili]

Nimeona ni vizuri tujikumbushe kidogo kuhusu Mtanzania huyu dadis aliyefungua fikra za wanataaluma wa sayansi. Ni ndefu lakini nafikiri ni muhimu.

Je watu kama Tanzania tuwaenzije?

========

The Mpemba effect is the observation that, in some specific, fairly common circumstances, hotter water freezes faster than colder water.

The effect is named for the Tanzanian high-school student Erasto B. Mpemba. Mpemba first encountered the phenomenon in the classroom of Eugene Marschall at Mkwawa Secondary (formerly High) School, Iringa, Tanzania, where Mpemba was a student. Eugene Marschall, a member of the Teachers for East Africa/TEA program, taught chemistry and physics at this school from 1965 to 1967. Mpemba first noticed the effect in 1963 after his account of the freezing of hot ice cream mix in cookery classes, and went on to publish experimental results with Dr. Denis G. Osborne in 1969.

At first sight, the behaviour seems contrary to thermodynamics. However, most thermodynamicists believe that each observation of the Mpemba effect can be explained with standard physical theory. Many effects can contribute to the observation, depending on the experimental set-up:

Different definition of freezing (Is it the physical definition of the point at which water forms a visible surface layer of ice, or the point at which the entire volume of water becomes a solid block of ice?)

Evaporation, reducing the volume to be frozen. Evaporation is endothermic.

Convection, accelerating heat transfers. Reduction of water density below 4°C tends to suppress the convection currents cooling the lower part of the liquid mass; the lower density of hot water would reduce this effect, perhaps sustaining the more rapid initial cooling.

The insulating effects of frost

The effect of boiling on dissolved gases

Supercooling. It is hypothesized that cold water, when placed in a freezing environment, supercools more than hot water in the same environment, thus solidifying slower than hot water. However, supercooling tends not to be significant where there are particles, which act as nuclei for ice crystals, thus precipitating rapid freezing.

The effect of solutes such as calcium and magnesium carbonate.

According to an article by Monwhea Jeng, there is no unique explanation yet for why, in some specific circumstances, hotter water freezes faster than colder water. The article makes no attempt to focus on the relevant transport phenomena concepts such as temperature and fluid flow fields. Indeed when temperature fields are introduced, the author states:

Analysis of the situation is now quite complex, since we are no longer considering a single parameter, but a scalar function, and computational fluid dynamics (CFD) is notoriously difficult. The greatest difficulties with CFD are with turbulent flow; with laminar (streamline) flow, as we have in this case, there is much better consistency between independent analyses, and a CFD analysis could be expected to be illuminating.

This effect is a heat transfer problem, therefore well suited to be studied from a transport phenomena viewpoint, based on continuum mechanics. When heat transfer is analyzed in terms of partial differential equations, whose solutions depend on a number of conditions, it becomes clear that measuring only a few lumped parameters, such as the water average temperature is generally insufficient to define the system behaviour, since conditions such as geometry, fluid properties and temperature and flow fields play an important role. The counterintuitiveness of the effect, if analyzed only in terms of simplified thermodynamics illustrates the need to include all the relevant variables and use the best available theoretical tools when approaching a physical problem.

Similar behavior may have been observed by ancient scientists such as Aristotle, and Early Modern scientists such as Francis Bacon and René Descartes. Aristotle's explanation involved a physical property he called antiperistasis, defined as "the supposed increase in the intensity of a quality as a result of being surrounded by its contrary quality". He used the concept of antiperistasis to provide evidence for his conjecture that human bodies and bodies of water were hotter in the winter than in the summer, a theory that was later disproved by Medieval and Renaissance observations.

Nimemsikiliza bwana Erasto B. MPEMBA clouds TV kuhusu maisha yake na ugunduzi wake aisee haki ya mungu kwa sayansi hii hatutaendelea na hatutapata wanasayansi wabobezi hasa bongo

 

[Ng'wanamangilingili]

Safi sana, hivi huyu Mpemba kabla ya hapo si aliwauliza watengeneza ice cream na wakamwambia wanaweka kwenye jokofu ikiwa ya moto.. Je unadhani hao watengeneza ice cream hawakuwai kuweka ya baridi lkn ikachelewa kuliko ya moto? Mpemba nadhani mchango weke ni pale alipoweza kuujurisha umma kuhusu ilo ila nadhani watengeneza Ice cream ndo chanzo

ugunduzi ndivyo ulivyo hata wewe unaweza umekalia ugunduzi hapo ulipo mwingine
atausemea

 

[expedition]

Education
In 1979, Mpemba was associated with the College of African Wildlife management - Mweka, Moshi, Tanzania.

 

[mzee jongo]

ugunduzi ndivyo ulivyo hata wewe unaweza umekalia ugunduzi hapo ulipo mwingine
atausemea

Hata Archimedes alifanya ugunduzi wakati anaoga ijapokua yeye co wakwanza kuoga ila ugunduzi ni pale unapoweza kujibu maswali haya juu ya udhani huo
HOW? WHY? And significance of it

 

[mzee jongo]

Kiukweli theory ni nzuri na yakipekee ila nauliza mpemba effe inafaida gani katika universe

 

[NANTUCHI]

Kiukweli theory ni nzuri na yakipekee ila nauliza mpemba effe inafaida gani katika universe

Huwezi kupata faida kabla ya kupata uthibitisho wa kisayansi. Mpemba aligundua lkn hakuweza kutoa maelezo ya kwa nn hutokea hvyo. Naamini mwisho angetengeneza formula ambayo ndio huwekwa ktk application.
Kinadharia mpemba effect ni Freezing is directly proportional to temperature...lzm atafute constant( unknown) ambayo angeita mpemba constant...! Angeprove hyo constant ndipo ingeweza kuingia ktk application kirahisi.

 

[mzee jongo]

Huwezi kupata faida kabla ya kupata uthibitisho wa kisayansi. Mpemba aligundua lkn hakuweza kutoa maelezo ya kwa nn hutokea hvyo. Naamini mwisho angetengeneza formula ambayo ndio huwekwa ktk application.
Kinadharia mpemba effect ni Freezing is directly proportional to temperature...lzm atafute constant( unknown) ambayo angeita mpemba constant...! Angeprove hyo constant ndipo ingeweza kuingia ktk application kirahisi.

Nimekuelewa sana mkuu

 

[Jenseny]

nimemwona leo clouds tv jamas analalamika sana ugunduzi wake umemnufaisha m criatia najiuliza hivi akina newton walinufaikaje!?

 

[shitabo]

Kuna watu wanabishana hapa kuhusu hii theory

 

[Jambazi]

Kwa kweli ikiwa kipimo cha akili za watu weusi dhidi ya wazungu ni katika vitu hivi, leo mimi nimedhihirisha kwamba hazimo kabisa maana nimeanzna kubisha hata maandishi kwamba si kweli, nikatolea mfano kwamba ni sawa na kulinganisha mbio za kiwete na mtu mzima kwamba atakaye tangulia kumaliza haraka kufika ni kiwete. Baadaye nikaona mada hii si utani ni kweli. Sasa je ni kweli sisi weusi kichwani ni finyu kuliko weupe hilo mimi nakata.

Huyu jamaa kwanini haenziwi???

 

[Sci-Fi]

Habarini wanabodi.

Jana katika pitapita zangu kwenye mitandao ya kijamii, twitter, nikakutana na kitu ambacho nilikua sikijui. Kwamba kuna mtanzania Ndugu, Erasto Mpemba, ndiye aliye gundua kuwa maji ya MOTO yanapoa haraka zaidi kuliko maji ya baaridi endapo yote yatawekwa kwenye jokofu!!!!

Swali langu ni kwanini hatukufundishwa hii kitu mashuleni, kwanini huyu ndugu Erasto Mpemba hakua promoted na serikali kiasi tukamjua na kutambua mchango wake kwa jamii ya kitanzania na dunia kwa ujumla?

Ninaimani kuna watanzania wengi ambao huwa wanafanya vitu vingi vizuri ila the same questions, huwa ni kwanini hawa jamaa huwa hawapewi promo na support na serikali yetu? Nilikwisha sikia na kuona watz wakitengeneza majenereta, ndege, radio, na vifaa vingine vya umeme kwa ujuzi wao binafsi ila baada ya hapo kimya kabisa...shida huwa ni nini??

Nadhani kuna umuhimu wa kuenzi na kuvipenda vyakwetu. Tuachane na Elimu ya kukaririshana kutoka kwenye mitaala ya wazungu inayoandaa waajiriwa badala ya watengeneza ajira.

Naomba kuwasilisha.

Asubuhi njema.

 

[Pain killer]

Tz ya viwonda,, mwambie agundue viwanda

 

[jingalao]

waandaji wa mitaala wana background za arts

 

[Ally humba]

Selikali yenyewe haijasoma vitu ivyo ,,vitapewa vipi kipaumbele ??[emoji53]

 

[Morgan Fisherman]

angekua mzungu wangemwita father of hot water freezes faster than cold water

 

[Dragoon]

Mtu mweusi hana thamani. angekuwa mwingereza ua mmarekani angesifika sana dunia nzima, na sisi tungemuweka katika mitaala yetu (kama tulivyoweka newton's law of motion, archmedes principle, darwin sijui nini nini...)

Tatizo ni mfumo wetu. elimu yetu inategemea sana mitaala ya wazungu, vitu vingi tunatoa kutoka kwao hasa kwa masuala ya sayansi. mwisho wa siku tunabaki kuwa inferior tu

 

[Ibrahim augustine]

Duhh ukweli mtupu