Izibonelo ezingu-20 zemibuzo ye-Thermodynamics
Inqubo ye-Thermodynamic
1. Ku-thermodynamics, igesi efanelekile idlula enkambisweni ye-isothermal uma…
A. izinguquko esimweni segesi, izinga lokushisa lihlala lingaguquki
B. wonke ama-molecule ahamba ngesivinini esihlukile
C. Zonke izimo zegesi zihlala zishintsha izinga lokushisa
D. emazingeni okushisa aphezulu ijubane lama-molecule liphakeme
Umfutho wegesi kanye nomthamo akushintshi
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I-Isothermal noma i-isothermic kusho izinga lokushisa elingaguquki.
Impendulo efanele ngu-A.
2. Wonke amagesi afanele adlula enkambisweni ye-isochoric ngakho...
A. wonke ama-molecule anejubane elifanayo
B. emazingeni okushisa aphezulu isivinini esimaphakathi sama-molecule sikhulu
C. umfutho wegesi uhlala ungaguquki
D. igesi izosebenza
I-E. ayinawo amandla angaphakathi
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Isochoric = ivolumu engaguquki.
Impendulo efanele ingu-B.
3. Isitatimende esifanele mayelana nezinqubo ze-thermodynamic sithi…
A. I-Isobaric inqubo yokushintsha igesi ngokucindezela okungaguquki.
B. I-Isobaric inqubo yokushintsha igesi ekushiseni okungaguquki.
C. I-Isochoric inqubo yokushintsha igesi ngokucindezela okungaguquki.
I-D. isotherm inqubo yokushintsha igesi ngevolumu engaguquki.
E. I-Isochoric inqubo yokushintsha igesi ekushiseni okungaguquki.
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Isobaric = ukucindezela okuqhubekayo
Isochoric = ivolumu engaguquki
Isothermal = izinga lokushisa elingaguquki
Impendulo efanele ngu-A.
Umthetho Wokuqala We-Thermodynamics
4. Kusukela kugrafu ye-PV engezansi, inani lomsebenzi wegesi ezinqubweni I kanye ne-II lilingana njengoba...
A. 4: 3
B. 3: 4
C. 2: 3
D. 1: 2
Isahluko 1: 1
Ingxoxo
Kuyaziwa ukuthi:
Inqubo 1:
Ingcindezi (P) = 20 N/m2
Ivolumu yokuqala (V)1) = amalitha ama-10 = ama-dm ama-103 = 10 x10-3 m3
Umqulu wokugcina (V)2) = amalitha ama-40 = ama-dm ama-403 = 40 x10-3 m3
Inqubo 2:
Ingcindezi (P) = 15 N/m2
Ivolumu yokuqala (V)1) = amalitha ama-20 = ama-dm ama-203 = 20 x10-3 m3
Umqulu wokugcina (V)2) = amalitha ama-60 = ama-dm ama-603 = 60 x10-3 m3
Kubuziwe:
Impendulo:
Umsebenzi wegesi uyaqhubeka I:
W = P ΔV = P (V)2-V1) = (20)(40-10)(10-3 m3) = (20)(30)(10-3 m3) = (600)(10-3 m3= 0,6m3
Umsebenzi wegesi uyaqhubeka II:
W = P ΔV = P (V)2-V1) = (15)(60-20)(10-3 m3) = (15)(40)(10-3 m3) = (600)(10-3 m3= 0,6m3
Ukuqhathaniswa komsebenzi wegesi ezinqubweni I kanye ne-II:
0,6 m3 : 0,6 m3
1: 1
Impendulo efanele ngu-E.
5. Kusukela kugrafu ye-P kuya ku-V, inani lomsebenzi wegesi ezinqubweni I kanye ne-II lilingana njengoba...
A. 4: 3
B. 3: 4
C. 2: 3
D. 1: 2
Isahluko 1: 1
Ingxoxo
Kuyaziwa ukuthi:
Inqubo I:
Ingcindezi (P) = 20 Pascal
Umqulu 1 (V)1) = amalitha ayi-10
Umqulu 2 (V)2) = amalitha ayi-40
Inqubo II:
Ingcindezi (P) = 15 Pascal
Umqulu 1 (V)1) = amalitha ayi-20
Umqulu 2 (V)2) = amalitha ayi-60
Kubuziwe: Ukuqhathaniswa komsebenzi wegesi ezinqubweni I kanye ne-II
Impendulo:
Inqubo ye-thermodynamic esekelwe kugrafu engenhla iyinqubo ye-isobaric (ukucindezela okuqhubekayo).
Umsebenzi owenziwe yigesi enqubweni yokuqala:
W = P (V)2 - V1)
W = (20)(40 – 10)
W = (20)(30)
W=600
Umsebenzi owenziwe yigesi enqubweni II:
W = P (V)2 - V1)
W = (15)(60 – 20)
W = (15)(40)
W=600
Ukuqhathaniswa komsebenzi wegesi ezinqubweni I kanye ne-II:
600: 600
1: 1
Impendulo efanele ngu-E.
6. Igesi ye-helium iyashiswa ngokwegrafu ye-PV engezansi. Umsebenzi owenziwe yigesi ye-helium enqubweni ye-AB...
A. 15 joule 
B. ama-joule ayi-10
C. 8 ama-joule
D. 4 ama-joule
E. 2 ama-joule
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I-Diketahui :
Ukucindezela (P) = 2 x 105 N / m2 = 2 x105 Easter
Ivolumu yokuqala (V)1= 5cm3 = 5 x10-6 m3
Umqulu wokugcina (V)2= 15cm3 = 15 x10-6 m3
Kubuziwe Umsebenzi owenziwe yigesi enqubweni AB
Jawab :
W = ∆P ∆V
W = P (V)2 - V1)
W = (2 x 105)(15 x 10-6 - 5 x 10-6)
W = (2 x 105)(10 x 10-6) = (2 x 105)(1 x 10-5)
W = 2 Joule
Impendulo efanele ngu-E.
7. Bheka isithombe! Igesi efanelekile idlula enkambisweni yokushintsha kwengcindezi (P) uma kuqhathaniswa nevolumu (V). Umsebenzi owenziwa yigesi kule nqubo…
A. 20 Joule
B. 15 Joule
C. 10 Joule
D. 5 Joule
E. 4 AmaJoule
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I-Diketahui :
Ingcindezi yokuqala (P)1) = 4 Pa = 4 N/m2
Ingcindezi yokugcina (P)2) = 6 Pa = 6 N/m2
Ivolumu yokuqala (V)1= 2m3
Umqulu wokugcina (V)2= 4m3
Kubuziwe Umsebenzi owenziwe yigesi (W)
Jawab :
Umsebenzi owenziwe ngegesi = indawo engaphansi kwejika ab.
W = indawo kanxantathu + indawo yesikwele
W = ½ (6-4)(4-2) + 4(4-2)
W = ½ (2)(2) + 4(2)
W = 2 + 8
W = 10 Joule
Impendulo efanele ngu-E.
8. Igesi efanelekile idlula enqubweni evaliwe A → B → C → A. Emjikelezweni, igesi isebenza cishe….
A. -2,0 x 103 J
B. -5,5 x 103 J
C. -8,0 x 105 J
D. 2,0 x 106 J
E. 4,0 x 106 J
Ingxoxo
Umsebenzi (W) = indawo yejika (indawo yenxantathu ngaphakathi komugqa ophawulwe ngomcibisholo).
W = ½ (20-10)(6 x 105 - 2 x 105)
W = ½ (10)(4 x 105)
W = (5)(4 x 105)
W = 20 x 105 = 2 x106 Joule
Impendulo efanele ngu-D.
Injini Yokushisa
9. Injini imunca amaJoules angu-2.000 okushisa avela endaweni yokugcina ukushisa okuphezulu bese yenqaba amaJoules angu-1.200 aye endaweni yokugcina ukushisa okuphansi. Ukusebenza kahle kwenjini ku ....
A. 80%
B. 75%
C. 60%
D. 50%
E. 40%
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Kuyaziwa ukuthi:
Ukushisa kuthathwe (Q)H) = amaJoules ayi-2000
Ukushisa kukhishwe (Q)L) = amaJoules ayi-1200
Umsebenzi owenziwe umshini (W) = 2000 – 1200 = 800 Joules
Kubuziwe : Ukusebenza kahle kwenjini yokushisa (e)
Jawab :
Ifomula yokusebenza kahle kwenjini yokushisa:
e = W / QH = 800/2000 = 0,4 x 100% = 40%
Impendulo efanele ngu-E.
Injini ye-Carnot
10. Ukusebenza kahle kwenjini yeCarnot enomjikelezo omunca ukushisa ekushiseni okungu-960 K futhi wenqabe ukushisa ekushiseni okungu-576 K...
A. 40%
B. 50%
C. 56%
D. 60%
E. 80%
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I-Diketahui :
Izinga lokushisa eliphezulu (T)H) = 960 K
Izinga lokushisa eliphansi (T)L) = 576 K
Kubuziwe Ukusebenza kahle kwenjini ye-Carnot (e)
Jawab :
Ukusebenza kahle kwenjini yeCarnot kungu-0,4 x 100% = 40%
Impendulo efanele ngu-A.
11. Kugrafu ye-PV yenjini yeCarnot engezansi, i-W = ama-Joules angu-6.000. Inani lokushisa elikhishwa yinjini ngomjikelezo ngamunye…
A. Ama-joule angu-2.250
B. ama-joule ayi-3.000
C. 3.750 ama-joule
D. 6.000 ama-joule
E. 9.600 ama-joule
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Kuyaziwa ukuthi:
Umsebenzi (W) = ama-Joules angu-6000
Izinga lokushisa eliphezulu (T)H) = 800 Kelvin
Izinga lokushisa eliphansi (T)L) = 300 Kelvin
Kubuziwe: Q
Impendulo:
Ukusebenza kahle kwenjini yokushisa efanele (injini yeCarnot):
Ukushisa okumuncwa yinjini yeCarnot:
W = e Q1
6000 = (0,625) Q1
Q1 = 6000/0,625
Q1 = 9600
Ukushisa okukhishwa yinjini yeCarnot:
Q2 =Q1 - W
Q2 = 9600 - 6000
Q2 = 3600 amaJoule
Ayikho impendulo efanele.
12. Injini yeCarnot esebenza kahle ngo-40% isebenzisa idamu elishisayo ku-727°C. Thola izinga lokushisa ledamu elibandayo!
A. 327°C
B. 357°C
C. 400°C
D. 600°C
E. 627°C
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Kuyaziwa ukuthi:
Ukusebenza kahle (e) = 40% = 40/100 = 0,4
Izinga lokushisa eliphezulu (T)H= = 727oC + 273 = 1000 K
Kubuziwe: Nquma izinga lokushisa ledamu elibandayo
Impendulo:
Izinga lokushisa ledamu lingu-600–273 = 327oC
Impendulo efanele ngu-A.
13. Igrafu ye-P-V yenjini yeCarnot ibukeka njengesithombe esilandelayo! Uma injini imunca ukushisa okungu-800 J, khona-ke umsebenzi owenziwe…
A. 105,5 J
B. 252,6 J
C. 336,6 J
D. 466,7 J
E. 636,7 J
Ingxoxo
Kuyaziwa ukuthi:
Izinga lokushisa eliphezulu (T)H) = 600 Kelvin
Izinga lokushisa eliphansi (T)L) = 250 Kelvin
Ukushisa kuthathwe (Q)1) = amaJoules ayi-800
Kubuziwe: Ibhizinisi (W)
Impendulo:
Ukusebenza kahle kwenjini yokushisa efanele (injini yeCarnot):
Imizamo eyenziwe yile:
W = e Q1
W = (7/12)(800 amaJoules)
W = 466,7 Joule
Impendulo efanele ngu-D.
14. Injini yeCarnot isebenza ekushiseni okuphezulu okungu-600 K ukuze ikhiqize umsebenzi womshini. Uma injini imunca ukushisa okungu-600 J ekushiseni okuphansi okungu-400 K, khona-ke umsebenzi okhiqizwayo….
A. 120 J
B. 124 J
C. 135 J
D. 148 J
E. 200 J
Ingxoxo
I-Diketahui :
Izinga lokushisa eliphansi (T)L) = 400 K
Izinga lokushisa eliphezulu (T)H) = 600 K
Ukushisa kuthathwe (Q)1) = amaJoules ayi-600
Kubuziwe Umsebenzi owenziwe yinjini yeCarnot (W)
Jawab :
Ukusebenza kahle kwenjini yokushisa efanele (injini yeCarnot):
Umsebenzi owenziwe yinjini yeCarnot:
W = e Q1
W = (1/3)(600) = 200 amaJoules
Impendulo efanele ngu-E.
I-Kinetic Theory yamagesi kanye ne-Thermodynamics
15. Ethangini kukhona igesi efanelekile enomthamo wamalitha ama-4, izinga lokushisa lingama-27oC kanye nokucindezela okungu-3 atm (1 atm = 105 I-Nm-2Igesi idlula enkambisweni yokushisa ngokucindezela okungaguquki kuze kufike ekushiseni okungu-87.oC. Umthamo wokushisa wegesi ungama-9 JK-1 . Umthamo wokugcina wegesi kanye noshintsho lwamandla angaphakathi egesi ngokulandelana…
A. 4,2 amalitha, ΔU = 200 amaJoule
B. 4,4 amalitha, ΔU = 240 amaJoule
C. 4,6 amalitha, ΔU = 280 amaJoule
D. 4,8 amalitha, ΔU = 300 amaJoule
E. 4,8 amalitha, ΔU = 360 amaJoule
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Inqubo ye-Isobaric (ingcindezi eqhubekayo)
Kuyaziwa ukuthi:
Umthamo wokuqala wegesi efanele (V)1) = amalitha ayi-4
Izinga lokushisa lokuqala legesi elifanele (T)1= = 27oC + 273 = 300 K
Izinga lokushisa lokugcina legesi elifanele (T)2= = 87oC + 273 = 360 K
Umfutho wegesi ofanele (P) = 3 atm = 3 x 105 I-Nm-2
Umthamo wokushisa wegesi (C) = 9 JK-1
Kubuziwe: Umthamo wokugcina wegesi (V)2) kanye noshintsho lwamandla kugesi (ΔU)
Impendulo:
Bala ivolumu yokugcina usebenzisa ifomula yomthethoum Charles (inqubo ye-isobaric noma yengcindezi engaguquki):
Ukushintsha kwevolumu:
Ilitha eli-1 = 0,001 m3
Ivolumu yokuqala (V)1) = 4 (0,001 m3= 0,004m3
Umqulu wokugcina (V)2) = 4,8 (0,001 m3= 0,0048m3
Shintsha vume (ΔV) = V2 - V1 = 0,0048 m3 - 0,004 m3 = 0,008m3.
Izinguquko Zokushisa:
Izinguquko zokushisa (ΔT) = T2 - T1 = 360 K – 300 K = 60 K
Bala ushintsho lwamandla angaphakathi (ΔU) wegesi efanelekile usebenzisa ifomula yoMthetho Wokuqala We-Thermodynamics:
ΔU = Q - W
Incazelo: ΔU = ushintsho emandleni angaphakathi, Q = ukushisa, W = umsebenzi.
Bala umsebenzi (W) ngokucindezela okungaguquki:
W = P ΔV = (3 x 105)(0,0008) = (3x101)(8) = (30)(8) = 240 amaJoule
Bala ukushisa (Q) usebenzisa ifomula yamandla okushisa (C):
C = Q / ΔT
Q = (C)(ΔT) = (9)(60) = 540 Joules
Bala ushintsho lwamandla angaphakathi:
ΔU = Q – W = 540 Joules – AmaJoules angu-240 = amaJoules angu-300.
Impendulo efanele ngu-D.
16. Ethangini kukhona amalitha ayi-6 egesi elifanele ngokucindezela okungu-2 atm (1 atm = 105 I-Nm-2), izinga lokushisa 27oC. Igesi ishiswa kufikela ku-77 degreesoC ngengcindezi engaguquki. Uma amandla okushisa egesi angama-5 JK-1, ivolumu yokugcina kanye noshintsho lwamandla angaphakathi egesi ngokulandelana….
A. amalitha angu-8; ΔU = 250 amaJoule
B. amalitha angu-8; ΔU = 200 amaJoule
C. amalitha angu-7; ΔU = 100 amaJoule
D. 7 amalitha; ΔU = 50 amaJoule
E. amalitha angu-7; ΔU = 20 amaJoule
Ingxoxo
Inqubo ye-Isobaric (ingcindezi eqhubekayo)
Kuyaziwa ukuthi:
Umthamo wokuqala wegesi efanele (V)1) = amalitha ayi-6
Izinga lokushisa lokuqala legesi elifanele (T)1= = 27oC + 273 = 300 K
Izinga lokushisa lokugcina legesi elifanele (T)2= = 77oC + 273 = 350 K
Umfutho wegesi ofanele (P) = 2 atm = 2 x 105 I-Nm-2
Umthamo wokushisa wegesi (C) = 5 JK-1
Kubuziwe: Umthamo wokugcina wegesi (V)2) kanye noshintsho lwamandla kugesi (ΔU)
Impendulo:
Bala ivolumu yokugcina usebenzisa ifomula yomthethoum Charles (inqubo ye-isobaric noma yengcindezi engaguquki):
Ukushintsha kwevolumu:
Ilitha eli-1 = 0,001 m3
Ivolumu yokuqala (V)1) = 6 (0,001 m3= 0,006m3
Vivolumu yokugcina (V)2) = 7 (0,001 m3= 0,007m3
Ukushintsha kwevolumu (ΔV) = V2 - V1 = 0,007m3 - 0,006 m3 = 0,001m3.
Izinguquko Zokushisa:
Izinguquko zokushisa (ΔT) = T2 - T1 = 350 K – 300 K = 50 K
Bala ushintsho lwamandla angaphakathi (ΔU) wegesi efanelekile usebenzisa ifomula yoMthetho Wokuqala We-Thermodynamics:
ΔU = Q - W
Incazelo: ΔU = ushintsho emandleni angaphakathi, Q = ukushisa, W = umsebenzi.
Bala umsebenzi (W) ngokucindezela okungaguquki:
W = P ΔV = (2 x 105)(0,001) = (2x102)(1) = (200)(1) = 200 amaJoules
Bala ukushisa (Q) usebenzisa ifomula yamandla okushisa (C):
C = Q / ΔT
Q = (C)(ΔT) = (5)(50) = 250 Joules
Bala ushintsho lwamandla angaphakathi:
ΔU = Q – W = 250 Joules – AmaJoules angu-200 = amaJoules angu-50.
Impendulo efanele ngu-D.
Inqubo ye-Thermodynamic
17. Naka igrafu eseceleni kanye nezitatimende ezilandelayo!
(1) Inqubo ye-AB iyi-isobaric kanti i-W = P (V)2 - V1)
(2) Inqubo i-BC i-adiabatic, kanti i-ΔU = Q
(3) Inqubo i-BC ayifani ne-isochoric, kanti i-ΔU = Q
(4) Inqubo ye-CA ayishisi kakhulu, futhi uhlelo lumunca ukushisa.
Isitatimende esinembile sithi…
A. (1) kanye no-(3)
B. (1) kanye no-(4)
C. (2) kanye no-(3)
D. (2) kanye (4)
E. (3) kanye no-(4)
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(1) Inqubo ye-AB iyi-isobaric kanti i-W = P (V)2 - V1)
Isobaric = ukucindezeleka okungaguquki. Ukucindezela okuqhubekayo kuboniswa umugqa oqondile eceleni kuka-P1 kusuka ku-A kuya ku-B. Kule nqubo, ingcindezi ihlala ingaguquki kodwa kukhona ushintsho kuvolumu lapho ivolumu ikhuphuka khona. Uma ivolumu ikhuphuka khona-ke uhlelo lusebenza endaweni ezungezile, lapho inani lomsebenzi (W) liwumphumela wokuphindaphinda ingcindezi (P) kanye noshintsho kuvolumu (ΔU).
(3) Inqubo i-BC ayifani ne-isochoric, kanti i-ΔU = Q
Isochoric = ivolumu engaguquki. Ivolumu engaguquki iboniswa umugqa oqondile eceleni kuka-V.2 kusuka ku-B kuya ku-C. Kule nqubo, ivolumu ihlala ingaguquki kodwa kukhona ushintsho ekucindezelweni lapho ingcindezi ikhuphuka khona. Ivolumu ayiguquki ngakho akukho msebenzi owenziwayo, lapho u-W = 0. Ifomula yoMthetho Wokuqala We-Thermodynamics ithi ΔU = Q – W, lapho u-ΔU = ushintsho emandleni angaphakathi, u-Q = ukushisa kanye no-W = umsebenzi. Uma kungekho msebenzi khona-ke u-W = 0, ngakho-ke u-ΔU = Q.
Impendulo efanele ngu-A.
18. Bheka igrafu elandelayo yomjikelezo we-thermodynamic!
Kusukela kulesi sitatimende esilandelayo:
(1) A – B = isochoric, umsebenzi uncike ekushintsheni kwezinga lokushisa
(2) B – C = adiabatic, akukho ukushintsha kokushisa
(3) B – C = isobaric, umsebenzi uncike ekushintsheni kwevolumu
(4) C – A = inqubo yenzeka ngomzamo ovela ngaphandle kohlelo
Iqiniso liwukuthi…
A. (1) kanye no-(2)
B. (1) kanye no-(3)
C. (2) kanye no-(3)
D. (2) kanye (4)
E. (3) kanye no-(4)
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(1) A – B = isochoric, umsebenzi uncike ekushintsheni kwezinga lokushisa
Yebo, le nqubo i-isochoric (ivolumu eqhubekayo). Kodwa-ke, ivolumu ihlala ingaguquki, ngakho-ke akukho msebenzi owenziwayo. Umsebenzi uyenzeka uma kukhona ushintsho lwevolumu. Ngakho-ke, lesi sitatimende asilungile.
(3) B – C = isobaric, umsebenzi uncike ekushintsheni kwevolumu
I-Isobaric = ingcindezi engaguquki. Ingcindezi engaguquki iboniswa umugqa oqondile ukusuka ku-B kuya ku-C. Kule nqubo, kuba noshintsho kuvolumu yesistimu, lapho ivolumu yesistimu ikhuphuka khona. Ukwanda kwevolumu yesistimu kusho ukuthi uhlelo lusebenza endaweni ezungezile.
(4) C – A = inqubo yenzeka ngomzamo ovela ngaphandle kohlelo
Kule nqubo, ivolumu yesistimu iyancipha futhi ingcindezi yesistimu iyancipha. Ukwehla kwevolumu yesistimu kusho ukuthi indawo iyasebenza ohlelweni. Ngamanye amazwi, umsebenzi wenziwa ngaphandle.
Impendulo efanele ngu-E.
Imithetho yeThermodynamics
19. Bheka isithombe! Igesi efanelekile idlula enkambisweni yokushintsha ingcindezi (P) ibe yivolumu (V). Umsebenzi owenziwa yigesi kule nqubo…
A. 20 Joule
B. 15 Joule
C. 10 Joule
D. 5 Joule
E. 4 AmaJoule
Ingxoxo
I-Diketahui :
Ingcindezi yokuqala (P)1) = 4 Pa = 4 N/m2
Ingcindezi yokugcina (P)2) = 6 Pa = 6 N/m2
Ivolumu yokuqala (V)1= 2m3
Umqulu wokugcina (V)2= 4m3
Kubuziwe Umsebenzi owenziwe yigesi (W)
Jawab :
Umsebenzi owenziwe ngegesi = indawo engaphansi kwejika ab.
W = indawo kanxantathu + indawo yesikwele
W = ½ (6-4)(4-2) + 4(4-2)
W = ½ (2)(2) + 4(2)
W = 2 + 8
W = 10 Joule
Impendulo efanele ngu-E.
20. Igesi efanelekile idlula enqubweni evaliwe A → B → C → A. Emjikelezweni, igesi isebenza cishe….
A. −2,0 x 103 J
B. −5,5 x 103 J
C. −8,0 x 105 J
D. 2,0 x 106 J
E. 4,0 x 106 J
Ingxoxo
Umsebenzi (W) = indawo yejika (indawo yenxantathu ngaphakathi komugqa ophawulwe ngomcibisholo).
W = ½ (20-10)(6 x 105 - 2 x 105)
W = ½ (10)(4 x 105)
W = (5)(4 x 105)
W = 20 x 105 = 2 x106 Joule
Impendulo efanele ngu-D.
Umthombo wombuzo:
Imibuzo Yefiziksi Yezivivinyo Zikazwelonke Zesikole Samabanga Aphezulu/Isikole Samabanga Aphezulu Sokufundela Umsebenzi
