Foromo ea Motheo ea Black
Molao-motheo oa Black ke mohopolo oa motheo fisiks o amanang le phetisetso ea mocheso. O hlahisitsoe ke Joseph Black, setsebi sa fisiks le setsebi sa k'hemistri sa Scotland sa lekholong la bo18 la lilemo. Ho bohlokoa ho utloisisa hore na mocheso o fetela joang ho tloha nthong e 'ngoe ho ea ho e 'ngoe 'me o na le lits'ebetso tse pharaletseng masimong a ho tloha boenjiniere ho isa saenseng ea tikoloho. Sengoloa sena se tla hlalosa mohopolo oa motheo oa Molao-motheo oa Black, lits'ebetso tsa oona, le ho fana ka mehlala e 'maloa e sebetsang ho fana ka kutloisiso e felletseng.
Mehopolo ea Motheo
Molao-motheo oa Black o amana le molao oa paballo ea matla moelelong oa phetisetso ea mocheso. Khopolo-taba ea mantlha ke hore ha lintho tse peli tse mochesong o fapaneng li kopana, mocheso o tla fetela ho tloha nthong e chesang ho ea nthong e pholileng ho fihlela li fihla tekanyong ea mocheso, ke hore, ha mocheso oa tsona o tšoana.
Ho ya ka dipalo, Foromo ya Molao-motheo wa Black e ka hlaloswa ka tsela ena:
\[ Q = m \cdot c \cdot \Delta T \]
Di mana:
– \( Q \) ke bongata ba mocheso o monngoang kapa o lokollotsoeng (ka li-joule, J)
– \( m \) ke boima ba ntho (ka dikhilogram, kg)
– \( c \) ke bokgoni bo itseng ba mocheso ba ntho (ka di-joule ka kilogram ka degree Celsius, J/kg°C)
– \( \Delta T \) ke phetoho mochesong oa ntho (ka likhato tsa Celsius, °C)
Foromo ena e kopanya diphetoho tse tharo tse kgolo phetisong ya mocheso: boima, bokgoni bo itseng ba mocheso, le phetoho ya mocheso. Bokgoni bo itseng ba mocheso (\(c \)) ke bongata ba matla a hlokahalang ho phahamisa mocheso wa kilogerama e le nngwe ya ntho ka degree e le nngwe ya Celsius.
Tšebeliso Bophelong ba Letsatsi le Letsatsi
Mokhoa oa motheo oa Black o na le lits'ebetso tse ngata tse sebetsang. Mohlala o mong ke ho fumana phetoho ea mocheso oa metsi ha a kopantsoe le leqhoa. Mohlala, haeba re batla ho tseba hore na ho hlokahala leqhoa le lengata hakae ho pholisa metsi a itseng, re ka sebelisa mokhoa ona.
Mohlala o mong ke boenjiniere ba mechini, moo baenjiniere ba hlokang ho utloisisa hore na mocheso o fetisetsoa joang ka har'a lienjene ho thibela ho chesa haholo. Kutloisiso e ntle ea Molao-motheo oa Black e lumella baenjiniere ho rala litsamaiso tse sebetsang hantle tsa ho pholisa.
Ho phaella moo, indastering ea lijo le lino, mokhoa ona o sebelisoa ho laola mocheso nakong ea ho pheha kapa ho boloka. Mohlala, lik'hamphani tsa ice cream li sebelisa molao-motheo oa phetisetso ea mocheso ho netefatsa hore lihlahisoa tsa tsona li lula li hoamisitsoe nakong ea kabo.
Mohlala oa Palo
Ho fana ka setšoantšo se hlakileng sa kamoo Foromo ea Molao-motheo o Motšo e sebelisoang kateng, mohlala oa lipalo ke ona:
A re re re na le 2 kg ya metsi ho 20°C, mme re batla ho phahamisa mocheso ho 100°C. Bokgoni bo ikgethang ba mocheso wa metsi ke 4.186 J/kg°C. Ho hlokahala matla a makae?
Ho sebelisa foromo:
\[ Q = m \cdot c \cdot \Delta T \]
Re nkela mekhoa e tsebahalang sebaka:
\[ Q = 2 \, \mongolo{kg} \metsotso 4.186 \, \mongolo{J/kg°C} \metsotso (100°C – 20°C) \]
\[ Q = 2 \, \mongolo{kg} \nako 4.186 \, \mongolo{J/kg°C} \nako 80°C \]
\[ Q = 669.76 \, \mongolo{kJ} \]
Kahoo, ho hlokahala 669.76 kJ ea matla ho phahamisa mocheso oa 2 kg ea metsi ho tloha ho 20°C ho ea ho 100°C.
Tekanyo ea Thermal
Tšebeliso e 'ngoe ea bohlokoa ea Molao-motheo oa Black ke ho utloisisa tekano ea mocheso. Ha lintho tse peli tse mochesong o fapaneng li kopana, li fapanyetsana mocheso ho fihlela li fihla tekanong ea mocheso. Nakong ena, mocheso oa lintho ka bobeli oa lekana, 'me ha ho na phetisetso ea mocheso e sa feleng lipakeng tsa tsona.
Khopolo ena e bohlokoa haholo mafapheng a mangata, ho kenyeletsoa boenjiniere, thuto ea tlelaemete, esita le baeloji. Mohlala, tsamaisong ea ho pholisa koloi, sesebelisoa sa ho pholisa le enjene li tla fihlela tekanyo ea mocheso ho thibela enjene ho chesa haholo.
Phello ea Bokhoni bo Ikhethang ba Mocheso
Bokgoni bo itseng ba mocheso (\(c\)) ba thepa ke ntlha ya bohlokwa ho etseng qeto ya hore na thepa e tla arabela jwang diphetohong tsa mocheso. Thepa e nang le bokgoni bo phahameng ba mocheso bo itseng e tla hloka matla a mangata ho fetola mocheso wa yona ho feta thepa e nang le bokgoni bo fokolang ba mocheso bo itseng.
Mohlala, metsi a na le bokgoni bo phahameng haholo ba mocheso, ho bolelang hore a ka monya kapa a lokolla mocheso o mongata ntle le ho ba le phetoho e kgolo mochesong. Ke ka lebaka leo metsi a atisang ho sebediswa e le setsidifatsi dikopong tse ngata, ho kenyeletswa le di-radiator tsa dikoloi le ditsamaiso tsa ho phodisa diplanti tsa motlakase.
Teko e Bonolo
Ho utloisisa Molao-motheo oa Black hamolemo, re ka etsa teko e bonolo lapeng. Mohlala, re ka kopanya metsi a chesang le a batang 'me ra lekanya mocheso oa ho qetela oa motsoako. Re sebelisa Molao-motheo oa Black, re ka bolela esale pele mocheso oa ho qetela 'me ra o bapisa le liphetho tsa liteko.
A re re re kopanya 1 kg ea metsi ho 80°C le 1 kg ea metsi ho 20°C. Re sebelisa molao-motheo oa tekano ea mocheso, re ka bala mocheso oa ho qetela oa motsoako. Kaha boima le matla a itseng a mocheso oa metsi lia tšoana, mocheso oa ho qetela o ka baloa e le karolelano ea mocheso oa pele:
\[ \text{Final temperature} = \frac{(m_1 \cdot T_1) + (m_2 \cdot T_2)}{m_1 + m_2} \]
\[ \text{Final temperature} = \frac{(1 \, \text{kg} \cdot 80°C) + (1 \, \text{kg} \cdot 20°C)}{1 \, \text{kg} + 1 \, \text{kg}} \]
\[ \text{Final temperature} = \frac{80 + 20}{2} \]
\[ \text{Mocheso oa ho qetela} = 50°C \]
Liteko tse kang tsena li thusa ho matlafatsa kutloisiso ea rona ea melao-motheo ea phetisetso ea mocheso le tekano ea mocheso.
Qetello
Molao-motheo oa Black ke khopolo-taba ea motheo fisiks e re thusang ho utloisisa hore na mocheso o fetela joang lipakeng tsa lintho. Ka ho kopanya boima, bokhoni bo itseng ba mocheso, le phetoho ea mocheso, re ka bala bongata ba matla a hlokahalang ho fetola mocheso oa ntho. Khopolo-taba ena e na le lits'ebetso tse pharaletseng bophelong ba letsatsi le letsatsi le masimong a fapaneng a indasteri.
Kutloisiso e ntle ea Molao-motheo oa Black e re lumella ho rala litsamaiso tse sebetsang hantle le ho utloisisa lits'ebetso tsa mocheso hamolemo. Re sebelisa mehlala e sebetsang le liteko tse bonolo, re ka bona bohlokoa ba molao-motheo ona likarolong tse fapaneng tsa bophelo ba rona.
