Ịghọta Ụkpụrụ Ndị Ojii
Ọ bụrụ na anyị agwakọta mmiri ọkụ na mmiri oyi n'ime akpa mepere emepe (dịka ọmụmaatụ, bọket), okpomọkụ na-esi na mmiri ọkụ ahụ aga na mmiri oyi. Ebe ọ bụ na akpa ahụ mepere emepe, ụfọdụ okpomọkụ na-aga na ikuku. Akpa ahụ na-adịkwa ọkụ. Okpomọkụ nke mmiri ọkụ na-ewepụta abụghị naanị mmiri oyi kamakwa ikuku na akpa ahụ na-amịkọrọ. N'ọnọdụ a, bọket ahụ bụ usoro na-anaghị anọpụ iche.
Mgbe anyị gwakọtara mmiri ọkụ na mmiri oyi n'ime thermos mechiri emechi, okpomọkụ na-esi na mmiri ọkụ gaa na mmiri oyi. thermos bụ usoro dịpụrụ adịpụ , yabụ okpomọkụ anaghị ebufe na ikuku ma ọ bụ thermos. Okpomọkụ nke mmiri ọkụ na-ewepụta na-abanye naanị na mmiri oyi ruo mgbe ngwakọta ahụ ruru nguzozi okpomọkụ.
Ụkpụrụ Black na-ekwu na n'ime sistemụ mechiri emechi nke dịpụrụ adịpụ, okpomọkụ nke ihe dị elu na-ewepụta = okpomọkụ nke ihe dị ala na-amịkọrọ.
Usoro isi nke ojii
Qgbanyụọ =Qserap
Nkọwa: Qgbanyụọ = okpomọkụ nke ihe dị elu na-ewepụta, Qserap = okpomọkụ nke ihe ndị dị ala na-amịkọrọ.
Ajụjụ ihe atụ nke isi ojii
1. Iberibe ígwè ọkụ nke nwere ibu nke 1 kg na okpomọkụ nke 100 oA na-etinye C n'ime akpa nwere mmiri nwere oke nke kilogram 2 na okpomọkụ nke 20 oC. Kedu okpomọkụ ikpeazụ nke ngwakọta ahụ? Okpomọkụ kpọmkwem nke ígwè = 450 J/kg Co, okpomọkụ mmiri kpọmkwem = 4200 J/kg Co.
Mkparịta ụka:
A maara :
ígwè m = 1 kg, Tbesi = 100 oC, m mmiri = 2 kg, Tikuku = 20 oC, c ígwè = 450 J/kg Co, c mmiri = 4200 J/kg Co.
A jụrụ :
Ngwakọta T?
Jawab :
Ígwè nwere okpomọkụ dị elu karịa mmiri, ya mere ígwè na-ewepụta okpomọkụ, mmiri na-amịkọrọ okpomọkụ.
(m)(c)(delta T) = (m)(c)(delta T)
(1)(450)(100-T) = (2)(4200)(T-20)
(450)(100-T) = (8400)(T-20)
45000 – 450T = 8400 T – 168000
45000 + 168000 = 8400 T + 450 T
213000 = 8850 T
T = 213000: 8850
T = 24 oC
Suhu Okpomọkụ ikpeazụ nke ngwakọta ígwè ọkụ na mmiri oyi mgbe ha abụọ nọ na nhazi okpomọkụ bụ 24 oC.
2. Ajụjụ nke 2015/2016 SMA/MA Physics National Examination Nke 20
A na-agwakọta gram 75 nke mmiri na okpomọkụ nke 0 o C na gram 50 nke mmiri ka okpomọkụ nke ngwakọta ahụ wee bụrụ 40 o C, yabụ okpomọkụ mbụ nke gram 50 nke mmiri bụ...
A. 125 o C
B. 120 o C
C. 110 o C
D. 100 o C
E. 80 o C
Mkparịta ụka
A maara na:
Mmiri dị n'ọbara 1 (m1 ) = gram 75
Okpomọkụ mbụ nke mmiri 1 (T 1 ) = 0 oC
Mmiri dị n'ọbara 2 (m2 ) = gram 50
Okpomọkụ ikpeazụ nke ngwakọta ahụ (T) = 40 oC
Ngụkọta nke oke ahụ bụ otu ihe ahụ, yabụ ọ dịghị mkpa ịgbanwe ya.
Achọrọ: Okpomọkụ mbụ nke mmiri 2 ( T2 )
Azịza:
Ụkpụrụ Black kwuru na n'ime sistemu mechiri emechi nke dịpụrụ adịpụ, okpomọkụ nke ihe dị elu na-ewepụta hà nhata okpomọkụ nke ihe dị ala na-amịkọrọ.
A tọhapụrụ Q = Q arapara
m 1 c ( Δ T 1 ) = m 2 c ( Δ T 2 )
Okpomọkụ mmiri kpọmkwem bụ otu ihe ahụ ya mere a na-ewepụ c na nha anya ahụ.
m 1 ( Δ T 1 ) = m 2 ( Δ T 2 )
(75)(40 – 0) = (50)(T 2 – 40)
(75)(40) = (50)(T 2 – 40)
3000 = 50 T 2 – 2000
3000 + 2000 = 50 T 2
5000 = 50 T 2
T2 = 100
Azịza ziri ezi bụ D.
3. Ajụjụ nke 2015/2016 SMA/MA Physics National Examination Nke 20
A na-ekpo ọkụ ígwè gram 200 ruo 120 oC wee tinye ya na gram 100 nke mmiri na okpomọkụ nke 30 oC . Mgbe nhazi ya gasịrị, okpomọkụ nke ngwakọta ahụ na-aghọ 60 oC . Ọ bụrụ na okpomọkụ mmiri kpọmkwem bụ 4200 J.kg -1 oC -1 , mgbe ahụ okpomọkụ kpọmkwem nke ígwè ahụ bụ...
A. 10,5 J.kg -1o C -1
B. 105 J.kg -1o C -1
C. 150 J.kg -1o C -1
D. 1050 J.kg -1o C -1
E. 1500 J.kg -1o C -1
Mkparịta ụka
Mgbanwe nke nkeji oke site na gram gaa na kilogram (Usoro Mba Nile nke nkeji)
A maara na:
Ọnụọgụ ígwè (m 1 ) = gram 200 = 0,2 kg
Okpomọkụ ígwè (T 1 ) = 120 oC
Mmiri dị n'ọbara (m2 ) = gram 100 = 0,1 kg
Okpomọkụ mmiri (T2 ) = 30 oC
Okpomọkụ ikpeazụ nke ngwakọta ahụ (T) = 60 oC
Okpomọkụ mmiri kpọmkwem (c2 ) = 4200 J.kg -1 o C -1
A jụrụ: Okpomọkụ kpọmkwem nke ígwè (c 1 )
Azịza:
A tọhapụrụ Q = Q arapara
m1 c1 (ΔT1) = m2 c2 (ΔT2)
(0,2)(c 1 )(120 – 60) = (0,1)(4200)(60 – 30)
(0,2)(c 1 )(60) = (0,1)(4200)(30)
12 c 1 = 12600
c 1 = 12600 / 12
c 1 = 1050
Azịza ziri ezi bụ D.
4. Ajụjụ Ule Mba nke 2018 maka Ụlọ Akwụkwọ Sekọndrị/Ụlọ Akwụkwọ Sekọndrị Ọrụ
A na-awụsa mmiri ọkụ 250 ml (100 oC ) n'ime ite nwere mmiri 400 ml na okpomọkụ nke 35 oC . Mgbe nhazi okpomọkụ gasịrị, okpomọkụ nke ngwakọta ahụ ga-adị… (okpomọkụ mmiri kpọmkwem 1,0 cal.gr -1 . o C -1 )
Mkparịta ụka
A maara:
Okpomọkụ mmiri ọkụ = 100 oC
Olu mmiri ọkụ = 250 ml = 0,25 lita = 0,25 dm 3 = (0,25)(1000 cm 3 ) = 250 cm 3
Okpomọkụ mmiri oyi = 35 oC
Olu mmiri oyi = 400 ml = 0,4 lita = 0,4 dm 3 = (0,4)(1000 cm 3 ) = 400 cm 3
Okpomọkụ mmiri kpọmkwem = 1,0 cal.gr -1 . o C -1
Njupụta mmiri = 1 gr/cm 3
Ajụrụ: Okpomọkụ ngwakọta
Azịza:
Gbakọọ oke mmiri ọkụ na oyi site na iji usoro njupụta:
m = ρ V
m = oke, ρ = njupụta, V = olu
Oke mmiri ọkụ: m = ρ V = ( 1 gr/cm 3 )(250 cm 3 ) = gram 250
Oke mmiri oyi: m = ρ V = ( 1 gr/cm 3 )(400 cm 3 ) = gram 400
Gbakọọ okpomọkụ nke ngwakọta ahụ site na iji usoro isi nke Black:
Okpomọkụ mmiri oyi na-amịkọrọ = okpomọkụ mmiri ọkụ na-ewepụta
mc Δ T = mc Δ T
Okpomọkụ kpọmkwem ahụ bụ otu ihe ahụ ya mere a na-ewepụ ya na nha anya ahụ.
m Δ T = m Δ T
(400)(T-35) = (250)(100-T)
400T – 14000 = 25000 – 250T
400T + 250T = 25000 + 14000
650T = 39000
T = 39000 / 650
T = 60 o C
