Mehlala e 20 ea Lipotso tsa Thermodynamics
Mokhoa oa Thermodynamic
1. Ho thermodynamics, khase e loketseng e feta ts'ebetsong ea isothermal haeba…
A. diphetoho boemong ba kgase, mocheso o dula o tsitsitse kamehla
B. limolek'hule tsohle li tsamaea ka lebelo le fapaneng
C. Maemo ohle a khase a lula a fetola mocheso
D. mochesong o phahameng lebelo la limolek'hule le phahame
Khatello ea khase ea E. le bophahamo ba modumo ha li fetohe
Puisano
Isothermal kapa isothermic e bolela mocheso o sa fetoheng.
Karabo e nepahetseng ke A.
2. Likhase tsohle tse ntle li feta ts'ebetsong ea isochoric kahoo ...
A. limolek'hule tsohle li na le lebelo le tšoanang
B. mochesong o phahameng lebelo le tloaelehileng la limolek'hule le leholo
Khatello ea khase ea C. e lula e tsitsitse
D. khase e tla sebetsa
E. ha e na matla a ka hare
Puisano
Isochoric = molumo o sa fetoheng.
Karabo e nepahetseng ke B.
3. Polelo e nepahetseng mabapi le lits'ebetso tsa thermodynamic ke…
A. Isobaric ke mokhoa oa ho fetola khase ka khatello e sa khaotseng.
B. Isobaric ke mokhoa oa ho fetola khase mochesong o sa fetoheng.
C. Isochoric ke mokhoa oa ho fetola khase ka khatello e sa khaotseng.
D. isotherm ke mokhoa oa ho fetola khase ka molumo o sa fetoheng.
E. Isochoric ke mokhoa oa ho fetola khase mochesong o sa fetoheng.
Puisano
Isobaric = khatello e sa khaotseng
Isochoric = molumo o sa fetoheng
Isothermal = mocheso o sa fetoheng
Karabo e nepahetseng ke A.
Molao oa Pele oa Thermodynamics
4. Ho tloha kerafong ea PV e ka tlase, palo ea mosebetsi oa khase lits'ebetsong tsa I le II e lekana le...
K. 4: 3
B. 3: 4
C. 2: 3
D. 1: 2
E. 1: 1
Puisano
Hoa tsebahala hore:
Mokhoa oa 1:
Khatello (P) = 20 N/m2
Molumo oa pele (V)1) = lilithara tse 10 = 10 dm3 = 10x10-3 m3
Moqolo oa ho qetela (V)2) = lilithara tse 40 = 40 dm3 = 40x10-3 m3
Mokhoa oa 2:
Khatello (P) = 15 N/m2
Molumo oa pele (V)1) = lilithara tse 20 = 20 dm3 = 20x10-3 m3
Moqolo oa ho qetela (V)2) = lilithara tse 60 = 60 dm3 = 60x10-3 m3
O botsitse:
Karabo:
Mosebetsi oa peterole o ntse o tsoela pele I:
W = P ΔV = P (V 2 –V 1 ) = (20)(40-10)(10 -3 m 3 ) = (20)(30)(10 -3 m 3 ) = (600)(10 -3 m 3 ) = 0,6 m 3
Mosebetsi oa khase o ntse o tsoela pele II:
W = P ΔV = P (V 2 –V 1 ) = (15)(60-20)(10 -3 m 3 ) = (15)(40)(10 -3 m 3 ) = (600)(10 -3 m 3 ) = 0,6 m 3
Papiso ea mosebetsi oa khase lits'ebetsong tsa I le II:
0,6 m 3 : 0,6 m 3
1: 1
Karabo e nepahetseng ke E.
5. Ho tloha grafeng ea P - V, palo ea mosebetsi oa khase lits'ebetsong tsa I le II e lekana joalo ka...
K. 4: 3
B. 3: 4
C. 2: 3
D. 1: 2
E. 1: 1
Puisano
Hoa tsebahala hore:
Ts'ebetso ea 1:
Khatello (P) = 20 Pascal
Buka ea 1 (V)1) = lilithara tse 10
Buka ea 2 (V)2) = lilithara tse 40
Mokhoa oa II:
Khatello (P) = 15 Pascal
Buka ea 1 (V)1) = lilithara tse 20
Buka ea 2 (V)2) = lilithara tse 60
O botsitse: Papiso ea mosebetsi oa khase lits'ebetsong tsa I le II
Karabo:
Ts'ebetso ea thermodynamic e thehiloeng ho kerafo e kaholimo ke ts'ebetso ea isobaric (khatello e sa khaotseng).
Mosebetsi o entsoeng ke khase o ntse o tsoela pele I:
W = P (V 2 – V 1 )
W = (20)(40 - 10)
W = (20)(30)
W = 600
Mosebetsi o entsoeng ke khase ts'ebetsong ea II:
W = P (V 2 – V 1 )
W = (15)(60 - 20)
W = (15)(40)
W = 600
Papiso ea mosebetsi oa khase lits'ebetsong tsa I le II:
600: 600
1: 1
Karabo e nepahetseng ke E.
6. Khase ea Heliamo e futhumatsoa ho latela kerafo ea PV e ka tlase. Mosebetsi o etsoang ke khase ea helium ts'ebetsong ea AB ke...
A. 15 joule 
B. 10 joule
C. 8 joule
D. 4 joule
E. 2 joule
Puisano
Hoa tsebahala hore :
Khatello (P) = 2 x 105 N / limithara2 = 2x105 Pascal
Molumo oa pele (V)1) = 5 cm3 = 5x10-6 m3
Moqolo oa ho qetela (V)2) = 15 cm3 = 15x10-6 m3
E botsitsoe Mosebetsi o entsoeng ke khase ts'ebetsong AB
Karabo :
W = ∆P ∆V
W = P (V 2 – V 1 )
W = (2 x 10 5 )(15 x 10 -6 – 5 x 10 -6 )
W = (2 x 10 5 )(10 x 10 -6 ) = (2 x 10 5 )(1 x 10 -5 )
W = 2 Joule
Karabo e nepahetseng ke E.
7. Sheba setšoantšo! Khase e loketseng e feta ts'ebetsong ea ho fetola khatello (P) khahlanong le bophahamo ba modumo (V). Mosebetsi o etsoang ke khase ts'ebetsong ena ke…
A. 20 Joule
B. 15 Joule
C. 10 Joule
D. 5 Joule
E. 4 Joule
Puisano
Hoa tsebahala hore :
Khatello ea pele (P)1) = 4 Pa = 4 N/m2
Khatello ea ho qetela (P)2) = 6 Pa = 6 N/m2
Molumo oa pele (V)1) = 2 m3
Moqolo oa ho qetela (V)2) = 4 m3
E botsitsoe : Mosebetsi o entsoeng ke khase (W)
Karabo :
Mosebetsi o etsoang ke khase = sebaka se ka tlas'a mothinya ab.
W = sebaka sa khutlotharo + sebaka sa khutlonnetsepa
W = ½ (6-4)(4-2) + 4(4-2)
W = ½ (2)(2) + 4(2)
W = 2 + 8
W = 10 Joule
Karabo e nepahetseng ke E.
8. Khase e loketseng e feta ts'ebetsong e koetsoeng A → B → C → A. Potolohong, khase e sebetsa ho fihlela ho….
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
Puisano
Mosebetsi (W) = sebaka sa mothinya (sebaka sa khutlotharo ka hare ho mola o tšoailoeng ka motsu).
W = ½ (20-10)(6 x 10 5 – 2 x 10 5 )
W = ½ (10)(4 x 10 5 )
W = (5)(4 x 10 5 )
W = 20 x 105 = 2x106 Joule
Karabo e nepahetseng ke D.
Enjene ea Mocheso
9. Enjene e monya li-Joules tse 2.000 tsa mocheso ho tsoa polokelong ea mocheso o phahameng 'me e hana li-Joules tse 1.200 ho ea polokelong ea mocheso o tlase. Bokhoni ba enjene ke ....
A. 80%
B. 75%
C. 60%
D. 50%
E. 40%
Puisano
Hoa tsebahala hore:
Mocheso o monyela (Q)H) = 2000 Joule
Mocheso o lokollotsoe (Q)L) = 1200 Joule
Mosebetsi o hlahisitsoeng ke mochini (W) = 2000 – 1200 = 800 Joules
E botsitsoe : Bokgoni ba enjene ya mocheso (e)
Karabo :
Foromo ea katleho ea enjene ea mocheso:
e = W / QH = 800/2000 = 0,4 x 100% = 40%
Karabo e nepahetseng ke E.
Enjene ea Carnot
10. Bokgoni ba enjene ea Carnot eo potoloho ea eona e monyang mocheso mochesong oa 960 K mme e hana mocheso mochesong oa 576 K ke...
A. 40%
B. 50%
C. 56%
D. 60%
E. 80%
Puisano
Hoa tsebahala hore :
Mocheso o phahameng (TH ) = 960 K
Mocheso o tlase (TL ) = 576 K
Potso : Bokgoni ba enjene ya carnot (e)
Karabo :
Bokgoni ba enjene ea Carnot ke 0,4 x 100% = 40%
Karabo e nepahetseng ke A.
11. Kharafong ea PV ea enjene ea Carnot ka tlase, W = 6.000 Joules. Palo ea mocheso o lokolloang ke enjene ka potoloho ke…
A. 2.250 joule
B. 3.000 joule
C. 3.750 joule
D. 6.000 joule
E. 9.600 joule
Puisano
Hoa tsebahala hore:
Mosebetsi (W) = 6000 Joule
Mocheso o phahameng (T)H) = 800 Kelvin
Mocheso o tlase (T)L) = 300 Kelvin
O botsitse: Q
Karabo:
Bokgoni ba enjene e futhumatsang e loketseng (enjene ea Carnot):
Mocheso o monngoang ke enjene ea Carnot:
W = e Q 1
6000 = (0,625) Q 1
Q1 = 6000/0,625
Q1 = 9600
Mocheso o lokolloang ke enjene ea Carnot:
P 2 = P 1 – W
Q 2 = 9600 – 6000
Q2 = 3600 Joule
Ha ho karabo e nepahetseng.
12. Enjene ea Carnot e nang le bokhoni ba 40% e sebelisa letamo le chesang ho 727°C. Fumana mocheso oa letamo le batang!
A. 327°C
B. 357°C
C. 400°C
D. 600°C
E. 627°C
Puisano
Hoa tsebahala hore:
Bokgoni (e) = 40% = 40/100 = 0,4
Mocheso o phahameng (T)H= 727oC + 273 = 1000 K
O botsitse: Fumana mocheso oa letamo le batang
Karabo:
Mocheso oa letamo ke 600–273 = 327oC
Karabo e nepahetseng ke A.
13. Kerafo ea P-V ea enjene ea Carnot e shebahala joalo ka setšoantšo se latelang! Haeba enjene e monya 800 J ea mocheso, joale mosebetsi o etsoang ke…
A. 105,5 J
B. 252,6 J
C. 336,6 J
D. 466,7 J
E. 636,7 J
Puisano
Hoa tsebahala hore:
Mocheso o phahameng (T)H) = 600 Kelvin
Mocheso o tlase (T)L) = 250 Kelvin
Mocheso o monyelang (Q 1 ) = 800 Joule
E botsitsoe: Boiteko (W)
Karabo:
Bokgoni ba enjene e futhumatsang e loketseng (enjene ea Carnot):
Maiteko a entsoeng ke:
W = e Q 1
W = (7/12)(800 Joule)
W = 466,7 Joule
Karabo e nepahetseng ke D.
14. Enjene ea Carnot e sebetsa mochesong o phahameng oa 600 K ho hlahisa mosebetsi oa mechini. Haeba enjene e monya 600 J ea mocheso mochesong o tlase oa 400 K, joale mosebetsi o hlahisoang ke….
A. 120 J
B. 124 J
C. 135 J
D. 148 J
E. 200 J
Puisano
Hoa tsebahala hore :
Mocheso o tlase (TL ) = 400 K
Mocheso o phahameng (TH ) = 600 K
Mocheso o monyelang (Q 1 ) = 600 Joule
Ho batloa : Mosebetsi o hlahisitsoeng ke enjene ea Carnot (W)
Karabo :
Bokgoni ba enjene e futhumatsang e loketseng (enjene ea Carnot):
Mosebetsi o entsoeng ke enjene ea Carnot:
W = e Q 1
W = (1/3)(600) = 200 Joule
Karabo e nepahetseng ke E.
Khopolo-taba ea Kinetic ea Likhase le Thermodynamics
15. Ka tankeng ho na le khase e loketseng e nang le bophahamo ba lilithara tse 4, mocheso oa 27oC le khatello ea 3 atm (1 atm = 105 Nm-2Khase e feta ts'ebetsong ea ho futhumatsa ka khatello e sa khaotseng ho fihlela mochesong oa 87 ℃.oC. Bokgoni ba mocheso ba khase ke 9 JK-1 Bophahamo ba ho qetela ba khase le phetoho ea matla a ka hare a khase ke…
A. Lilithara tse 4,2, ΔU = 200 Joule
B. Lilithara tse 4,4, ΔU = 240 Joule
C. Lilithara tse 4,6, ΔU = 280 Joule
D. Lilithara tse 4,8, ΔU = 300 Joule
E. Lilithara tse 4,8, ΔU = 360 Joule
Puisano
Ts'ebetso ea Isobaric (khatello e sa khaotseng)
Hoa tsebahala hore:
Bophahamo ba pele ba khase e loketseng (V)1) = lilithara tse 4
Mocheso oa pele oa khase e loketseng (T)1= 27oC + 273 = 300 K
Mocheso oa ho qetela oa khase e loketseng (T)2= 87oC + 273 = 360 K
Khatello e loketseng ea khase (P) = 3 atm = 3 x 105 Nm-2
Bokgoni ba mocheso ba khase (C) = 9 JK-1
O botsitse: Bophahamo ba ho qetela ba khase (V)2) le Phetoho ea matla khaseng (ΔU)
Karabo:
Bala palo ea ho qetela u sebelisa foromo ea molaoum Charles (ts'ebetso ea isobaric kapa khatello e sa khaotseng):
Phetoho ea Molumo:
Litara e le 1 = 0,001 m 3
Molumo oa pele (V)1) = 4 (0,001 m3) = 0,004 m3
Moqolo oa ho qetela (V)2) = 4,8 (0,001 m3) = 0,0048 m3
Phetoho vlume (ΔV) = V2 - V1 = 0,0048 limithara3 - 0,004 limithara3 = 0,008 limithara3.
Liphetoho tsa mocheso:
Liphetoho tsa mocheso (ΔT) = T2 - T1 = 360 K – 300 K = 60 K
Bala phetoho ea matla a ka hare (ΔU) a khase e loketseng u sebelisa foromo ea Molao oa Pele oa Thermodynamics:
ΔU = Q – W
Tlhaloso: ΔU = phetoho ea matla a ka hare, Q = mocheso, W = mosebetsi.
Bala mosebetsi (W) ka kgatello e sa fetoheng:
W = P ΔV = (3 x 105)(0,0008) = (3x101)(8) = (30)(8) = 240 Joule
Bala mocheso (Q) o sebedisa foromo ya bokgoni ba mocheso (C):
C = Q / ΔT
Q = (C) (ΔT) = (9) (60) = 540 Joules
Bala phetoho ea matla a ka hare:
ΔU = Q – W = 540 Joule – Li-joule tse 240 = Li-joule tse 300.
Karabo e nepahetseng ke D.
16. Ka tankeng ho na le lilithara tse 6 tsa khase e loketseng ka khatello ea 2 atm (1 atm = 105 Nm-2), mocheso 27oC. Khase e futhumatsoa ho fihlela mochesong oa likhato tse 77oC ka kgatello e sa fetoheng. Haeba bokgoni ba mocheso ba kgase e le 5 JK-1, bophahamo ba ho qetela le phetoho ea matla a ka hare a khase ke ka ho latellana….
A. Lilithara tse 8; ΔU = 250 Joule
B. lilithara tse 8; ΔU = 200 Joule
C. lilithara tse 7; ΔU = 100 Joule
D. 7 lilithara; ΔU = 50 Joule
E. lilithara tse 7; ΔU = 20 Joule
Puisano
Ts'ebetso ea Isobaric (khatello e sa khaotseng)
Hoa tsebahala hore:
Bophahamo ba pele ba khase e loketseng (V)1) = lilithara tse 6
Mocheso oa pele oa khase e loketseng (T)1= 27oC + 273 = 300 K
Mocheso oa ho qetela oa khase e loketseng (T)2= 77oC + 273 = 350 K
Khatello e loketseng ea khase (P) = 2 atm = 2 x 105 Nm-2
Bokgoni ba mocheso ba khase (C) = 5 JK-1
O botsitse: Bophahamo ba ho qetela ba khase (V)2) le Phetoho ea matla khaseng (ΔU)
Karabo:
Bala palo ea ho qetela u sebelisa foromo ea molaoum Charles (ts'ebetso ea isobaric kapa khatello e sa khaotseng):
Phetoho ea Molumo:
Litara e le 1 = 0,001 m 3
Molumo oa pele (V)1) = 6 (0,001 m3) = 0,006 m3
Vmoqolo oa ho qetela (V)2) = 7 (0,001 m3) = 0,007 m3
Phetoho ea molumo (ΔV) = V2 - V1 = 0,007 limithara3 - 0,006 limithara3 = 0,001 limithara3.
Liphetoho tsa mocheso:
Liphetoho tsa mocheso (ΔT) = T2 - T1 = 350 K – 300 K = 50 K
Bala phetoho ea matla a ka hare (ΔU) a khase e loketseng u sebelisa foromo ea Molao oa Pele oa Thermodynamics:
ΔU = Q – W
Tlhaloso: ΔU = phetoho ea matla a ka hare, Q = mocheso, W = mosebetsi.
Bala mosebetsi (W) ka kgatello e sa fetoheng:
W = P ΔV = (2 x 105)(0,001) = (2x102(1)) = (200)(1) = 200 Joule
Bala mocheso (Q) o sebedisa foromo ya bokgoni ba mocheso (C):
C = Q / ΔT
Q = (C) (ΔT) = (5) (50) = 250 Joules
Bala phetoho ea matla a ka hare:
ΔU = Q – W = 250 Joule – Li-joule tse 200 = Li-joule tse 50.
Karabo e nepahetseng ke D.
Mokhoa oa Thermodynamic
17. Ela hloko kerafo e ka lehlakoreng le lipolelo tse latelang!
(1) Ts'ebetso ea AB ke isobaric mme W = P (V)2 - V1)
(2) Ts'ebetso ea BC ke adiabatic, 'me ΔU = Q
(3) Ts'ebetso ea BC ke ea isochoric, 'me ΔU = Q
(4) Ts'ebetso ea CA ha e chese haholo, 'me sistimi e monya mocheso.
Polelo e nepahetseng ke…
A. (1) le (3)
B. (1) le (4)
C. (2) le (3)
D. (2) le (4)
E. (3) le (4)
Puisano
(1) Ts'ebetso ea AB ke isobaric mme W = P (V)2 - V1)
Isobaric = khatello e sa khaotseng. Khatello e sa khaotseng e bontšoa ke mola o otlolohileng ho latela P1 ho tloha ho A ho ea ho B. Ts'ebetsong ena, khatello e lula e tsitsitse empa ho na le phetoho ea molumo moo molumo o eketsehang. Haeba molumo o eketseha, sistimi e sebetsa tikolohong, moo bongata ba mosebetsi (W) bo bakoang ke ho atisa khatello (P) le phetoho ea molumo (ΔU).
(3) Ts'ebetso ea BC ke ea isochoric, 'me ΔU = Q
Isochoric = bophahamo ba modumo bo sa fetoheng. Bolumo bo sa fetoheng bo bontshwa ka mola o otlolohileng ho latela V.2 ho tloha ho B ho ea ho C. Ts'ebetsong ena, bophahamo ba modumo bo lula bo tsitsitse empa ho na le phetoho khatellong moo khatello e eketsehang. Bophahamo ba modumo bo tsitsitse kahoo ha ho mosebetsi o etsoang, moo W = 0. Foromo ea Molao oa Pele oa Thermodynamics ke ΔU = Q – W, moo ΔU = phetoho matla a ka hare, Q = mocheso le W = mosebetsi. Haeba ho se na mosebetsi joale W = 0, kahoo ΔU = Q.
Karabo e nepahetseng ke A.
18. Sheba kerafo e latelang ea potoloho ea thermodynamic!
Ho tsoa polelong e latelang:
(1) A – B = isochoric, mosebetsi o itshetlehile ka diphetoho mochesong
(2) B – C = adiabatic, ha ho na phetoho ya mocheso
(3) B – C = isobaric, mosebetsi o itshetlehile ka diphetoho tsa bophahamo ba modumo
(4) C – A = tshebetso e etsahala ka boiteko bo tswang kantle ho sistimi
'Nete ke hore…
A. (1) le (2)
B. (1) le (3)
C. (2) le (3)
D. (2) le (4)
E. (3) le (4)
Puisano
(1) A – B = isochoric, mosebetsi o itshetlehile ka diphetoho mochesong
E, ts'ebetso ena ke isochoric (molumo o sa fetoheng). Leha ho le jwalo, molumo o dula o tsitsitse, kahoo ha ho mosebetsi o etswang. Mosebetsi o etsahala ha ho na le phetoho molumong. Ka hona, polelo ena ha e a nepahala.
(3) B – C = isobaric, mosebetsi o itshetlehile ka diphetoho tsa bophahamo ba modumo
Isobaric = kgatello e sa fetoheng. Kgatello e sa fetoheng e bontshwa ke mola o otlolohileng ho tloha ho B ho ya ho C. Mokgweng ona, ho na le phetoho bophahamong ba sistimi, moo bophahamo ba sistimi bo eketsehang. Keketseho bophahamong ba sistimi e bolela hore sistimi e sebetsa tikolohong.
(4) C – A = tshebetso e etsahala ka boiteko bo tswang kantle ho sistimi
Mokgweng ona, bophahamo ba sistimi bo a fokotseha mme kgatello ya sistimi e a fokotseha. Ho fokotseha ha bophahamo ba sistimi ho bolela hore tikoloho e sebetsa tsamaisong. Ka mantsoe a mang, mosebetsi o etswa kantle.
Karabo e nepahetseng ke E.
Melao ea Thermodynamics
19. Sheba setšoantšo! Khase e loketseng e feta ts'ebetsong ea ho fetola khatello (P) ho ea ho bophahamo ba modumo (V). Mosebetsi o etsoang ke khase ts'ebetsong ena ke…
A. 20 Joule
B. 15 Joule
C. 10 Joule
D. 5 Joule
E. 4 Joule
Puisano
Hoa tsebahala :
Khatello ea pele (P)1) = 4 Pa = 4 N/m2
Khatello ea ho qetela (P)2) = 6 Pa = 6 N/m2
Molumo oa pele (V)1) = 2 m3
Moqolo oa ho qetela (V)2) = 4 m3
E botsitsoe : Mosebetsi o entsoeng ke khase (W)
Jawab :
Mosebetsi o etsoang ke khase = sebaka se ka tlas'a mothinya ab.
W = sebaka sa khutlotharo + sebaka sa khutlonnetsepa
W = ½ (6-4)(4-2) + 4(4-2)
W = ½ (2)(2) + 4(2)
W = 2 + 8
W = 10 Joule
Karabo e nepahetseng ke E.
20. Khase e loketseng e feta ts'ebetsong e koetsoeng A → B → C → A. Potolohong, khase e sebetsa ho fihlela ho….
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
Puisano
Mosebetsi (W) = sebaka sa mothinya (sebaka sa khutlotharo ka hare ho mola o tšoailoeng ka motsu).
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 = 2x106 Joule
Karabo e nepahetseng ke D.
Mohloli oa lipotso:
Lipotso tsa Fisiks tsa Tlhahlobo ea Naha bakeng sa Sekolo se Phahameng sa Thuto e Phahameng/Sekolo se Phahameng sa Mosebetsi
