Mehlala e 20 ea Melao ea Newton
Molao oa Pele oa Newton
1. Haeba matla a hlahang a sebetsang nthong a lekana le lefela, joale...
(1) ntho e ke ke ea potlakisa
(2) lintho li lula li phomotse
(3) phetoho lebelong la ntho ke lefela
(4) ho ke ke ha khoneha hore ntho e tsamaee ka mola o otlolohileng ka lebelo le sa fetoheng
'Nete ke hore ...
A. (1), (2) le (3)
B. (1) le (3) feela
C. (2) le (4) feela
D. (4) feela
E. (1), (2), (3) le (4)
Puisano
Karabo e nepahetseng ke:
(1) Ntho e ke ke ea potlakisa
Matla a hlahang a etsa hore ntho e potlake. Haeba matla a hlahang e le lefela, ntho e ke ke ea potlaka.
(2) Lintho li lula li phomotse
Molao oa Pele oa Newton o re haeba matla a hlahang a sebetsang nthong a lekana le lefela, joale ntho e phomotseng e tla lula e phomotse ' me ntho e tsamaeang ka lebelo le sa fetoheng (motsamao o ts'oanang oa mola) e tla lula e tsamaea ka lebelo le sa fetoheng.
(3) Phetoho lebelong la ntho ke lefela
Phetoho lebelong = ho potlaka. Phetoho lebelong la ntho ke lefela, ho bolelang hore ho potlaka ha ntho ke lefela. Haeba ho potlaka e le lefela, joale matla a hlahang a sebetsang nthong ke lefela.
Karabo e nepahetseng ke A.
Lintho tse ka Lifting
2. Ha Sandi a le ka har'a lifti e sa sisinyeheng, boima ba hae ke 500 N. Ho potlaka ho bakoang ke matla a khoheli = 10 ms –2 . Ha lifti e potlaka, khatello thapong e ba 750 N. Kahoo, ho potlaka ha lifti ke…
A. 5,0 ms –2
B. 7,5 ms –2
C. 10,0 ms –2
D. 12,5 ms –2
E. 15,0 ms –2
Puisano
Hoa tsebahala hore:
Boima ba khoutu (w) = 500 Newton = 500 kg ms –2 (lifti e phomotseng)
Ho potlaka ka lebaka la matla a khoheli (g) = 10 ms –2
Boima ba Phasewete (m) = 500 / 10 = 50 kg
Kgatelelo ya thapo (T) = 750 N (lifti e potlakisitswe)
Boima ba lifti bo hlokomolohuoa.
E botsitsoe: Ho potlaka ha lifti
Karabo:
Lifti e phomotse, ha ho na ho potlaka (a = 0). Matla a hodimo a matle, matla a ho theoha a mabe.
ΣF = ma
T – w = 0
T = w
T = 500 Newton
Haeba phaephe e potlaka ho ya tlase, matla a kgatello thapong a ba ka tlase ho di-Newton tse 500. Ka lehlakoreng le leng, haeba phaephe e potlakiswa ho ya hodimo, matla a kgatello thapong a ba maholo ho feta di-Newton tse 500.
Kgatelelo ya thapo e fetoha 750 N, e leng se etsang hore lifti e potlakele ho ya hodimo. Matla a ka lehlakoreng le le leng le motsamao wa lifti a matle, mme matla a ka lehlakoreng le leng a mabe.
T – w = ma
750 – 500 = 50 a
250 = 50 a
a = 250/50
a = 5,0 ms –2
Karabo e nepahetseng ke A.
3. Motho ea boima ba 60 kg o ka har'a lifti e theohelang tlase ka lebelo la 3 ms -2 . Haeba lebelo le bakoang ke matla a khoheli e le 10 ms -2 , joale boholo ba matla a tloaelehileng a sebelisoang ke mokatong oa lifti ho motho ke...
A. 180 N
B. 200 N
C. 340 N
D. 420 N
E. 600 N
Puisano
Hoa tsebahala hore:
Boima (m) = 60 kg
Ho potlaka ha motho le lifti (a) = 3 m/s 2
Ho potlaka ka lebaka la matla a khoheli (g) = 10 m/s 2
Matla a khoheli (w) = mg = (60)(10) = 600 Newtons
E botsitsoe: matla a tloaelehileng (N)
Karabo:
Ho na le matla a mabeli a sebetsang ho motho ea ka har'a lifti, e leng matla a khoheli (w) le matla a tloaelehileng a sebelisoang ke mokatong oa lifti ho motho (N). Ho na le bongata ba vector bo tharo, e leng matla a khoheli, matla a tloaelehileng, le ho potlakisa lifti, moo matla a khoheli a lebisitsoeng tlase, matla a tloaelehileng a lebisitsoeng holimo, 'me ho potlakisa lifti ho lebisitsoeng tlase. Bongata ba vector bo lebisitsoeng tlase bo khethoa hore bo be le letšoao le letle 'me bongata ba vector bo lebisitsoeng holimo bo khethoa hore bo be le letšoao le lebe.
∑ F = ma
w – N = (60)(3)
600 – N = 180
N = 600 – 180
N = 420 Newton
Karabo e nepahetseng ke D.
4. Reza, ea boima ba 40 kg, o ka har'a lifti e nyolohelang holimo. Haeba matla a mokatong oa lifti maotong a Reza e le 520 N 'me lebelo le bakoang ke matla a khoheli e le 10 ms -2 , joale lebelo la lifti ke...
A. 1,0 ms -2
B. 1,5 ms -2
C. 2,0 ms -2
D. 2,5 ms -2
E. 3,0 ms -2
Puisano
Hoa tsebahala hore:
Boima (m) = 40 kg
Matla a tloaelehileng (N) = 520 N
Ho potlaka ka lebaka la matla a khoheli (g) = 10 m/s 2
Matla a khoheli (w) = mg = (40)(10) = 400 N
E botsitsoe: Ho potlaka ha lifti
Karabo:
∑ F = ma
400 – 520 = (40)(a)
-120 = (40)(a)
a = -120/40
a = -3 m/s 2
Ho potlaka ha lifti ke 3 m/s 2. Letšoao le lebe le bolela hore lifti e ea holimo.
5. Motho ea boima ba 60 kg o ka har'a lifti e theohelang tlase ka lebelo la 3 ms -2 . Maoto a batho a na le khatello e kae fatše ka har'a lifti?
Puisano
Hoa tsebahala hore:
Boima ba motho (m) = 60 kg
Boima ba motho (w) = mg = (60 kg)(10 m/s 2 ) = 600 kg m/s 2 = 600 Newtons
Ho potlaka ha lifti (a) = 3 m/s 2 , ho theohela tlase.
E botsitsoe: Maoto a motho a na le kgatello e kae fatshe ho lifti?
Karabo:
Lifti e theohela tlase ka lebelo la (a) la 3 m/s 2. Matla a ka lehlakoreng le le leng le motsamao wa lifti a matle, matla a ka lehlakoreng le fapaneng le motsamao wa lifti a matle.
w – N = ma
N = w – ma
N = 600 – (60)(3)
N = 600 – 180
N = 420 Newton
Ena ke matla a tloaelehileng ao mokatong oa lifti o a sebelisang ho motho. Motho o eme a eme holim'a lifti hoo boholo ba matla a tloaelehileng bo lekanang le boima ba motho bo bonahalang. Boima bo bonahalang bo lekana le khatello ea maoto a motho fatše.
Sistimi ea ho Jara Rope ea Pulley
6. Lintho tse peli A le B, e 'ngoe le e 'ngoe e nang le boima ba 6 kg le 2 kg, li tlamiloe ka thapo holim'a pulley joalo ka ha ho bontšitsoe setšoantšong. Haeba khohlano pakeng tsa thapo le pulley e hlokomolohuoa 'me g = 10 ms -2 , joale tsitsipano thapong ke...
A. 20 N
B. 24 N
C. 27 N
D. 30 N
E. 50 N
Puisano
Hoa tsebahala hore:
m A = 6 kg, m B = 2 kg, g = 10 m/s 2
w A = m A g = (6 kg)(10 m/s 2 ) = 60 kg m/s 2
w B = m B g = (2 kg)(10 m/s 2 ) = 20 kg m/s 2
Potso: Matla a kgatello ya thapo (T) ke afe?
Karabo:
w A > w B ka hona sistimi e tsamaya ka lehlakoreng le leng (m A e theohela tlase, m B e nyolohela hodimo).
Ho potlaka
ΣF = ma
w A – w B = (m A + m B ) a
60 – 20 = (6 + 2) a
40 = (8) a
a = 40 / 8 = 5 m/s 2
Khatello ea thapo
m A e theohela tlase
w A – T A = m A a
60 – T A = (6)(5)
60 – TA = 30
TA = 60 - 30
T 2 = 30 Newton
m B e nyolohela holimo
T B – w B = m B a
T B – 20 = (2)(5)
T B – 20 = 10
T B = 10 + 20
T 1 = 30 Newton
Kgatelelo ya thapo (T) = 30 Newtons.
Karabo e nepahetseng ke D.
7. Sheba setšoantšo ka lehlakoreng! Khohlano ea thapo le pulley e hlokomolohuoa. Haeba boima A = 5 kg, g = 10 ms s —2 le A li theohela tlase ka lebelo la 2,5 ms s —2 , joale boima ba B ke bokae?
A. 0,5 kg
B. 1 kg
C. 1,5 kg
D. 2 kg
E. 3 kg
Puisano
Hoa tsebahala hore:
Boima A (m A ) = 5 kg
Ho potlaka ka lebaka la matla a khoheli (g) = 10 m/s 2
Ho potlaka ha A kapa ho potlaka ha sistimi (a) = 2,5 m/s 2
Boima A (w A ) = (m A )(g) = (5)(10) = 50 Newtons
Botsitswe: boima ba B (m B ) ke bokae?
Karabo:
Block A e theohela tlase ka hona boima ba A (w A ) bo boholo ho feta boima ba B (w B ).
Sebelisa molao oa bobeli oa Newton:
ΣF = ma
w A – w B = (m A + m B ) a
50 – (m B )(10) = (5 + m B ) (2,5)
50 – 10 m B = 12,5 + 2,5 m B
50 – 12,5 = 2,5 m B + 10 m B
37,5 = 12,5 m B
m B = 3 kg
Karabo e nepahetseng ke E.
8. Lintho tse peli tse boima ba 2 kg le 3 kg li tlangwa ka thapo ebe li hokeloa ho pulley eo boima ba eona bo hlokomolohuoang joalo ka ha ho bontšitsoe setšoantšong.
Haeba boholo ba ho potlaka ha matla a khoheli = 10 ms -2 , matla a khatello a thapo a bonoang ke sistimi ke....
A. 20 N
B. 24 N
C. 27 N
D. 30 N
E. 50 N
Puisano
Hoa tsebahala hore:
m 1 = 2 kg, m 2 = 3 kg, g = 10 m/s 2
w 1 = (m 1 )(g) = (2 kg)(10 m/s 2 ) = 20 kg m/s 2 kapa 20 Li-Newton
w 2 = (m 2 )(g) = (3 kg)(10 m/s 2 ) = 30 kg m/s 2 kapa 30 Li-Newton
Potso: Matla a kgatello ya thapo (T) ke afe?
Karabo:
w 2 > w 1 ka hona sistimi e tsamaya ka ho leba ho ya ka watjhe (m 2 e theohela tlase, m 1 e nyolohela hodimo).
Ho potlaka
ΣF = ma
w 2 – w 1 = (m 1 + m 2 ) a
30 – 20 = (2 + 3) a
10 = (5) a
a = 10 / 5 = 2 m/s 2.
Khatello ea thapo
m2 e theohela tlase
w 2 – T 2 = m 2 a
30 – T 2 = (3)(2)
30 – T 2 = 6
T 2 = 30 – 6
T 2 = 24 Newton
m 1 e nyolohela holimo
T 1 – w 1 = m 1 a
T 1 – 20 = (2)(2)
T 1 – 20 = 4
T 1 = 20 + 4
T 1 = 24 Newton
Kgatelelo ya thapo (T) = 24 Newtons.
Karabo e nepahetseng ke B.
9. Liboloko tse peli li hokahantsoe ka pulley e boreleli 'me boima ba pulley bo hlokomolohuoa joalo ka ha ho bontšitsoe setšoantšong. Boima A = m A , boima B = m B le boloko B bo oa ka ho potlaka a. Haeba potlaka ka lebaka la matla a khoheli e le g, joale boholo ba tsitsipano ea thapo e hlahang bolokong B ke…
A. T = mB.a
B. T = m A (a – g)
C. T = m A (g – a)
D. T = m B (a – g)
E. T = m B (g – a)
Puisano
Bokaholimo bo bataletseng bo boreleli kahoo ha ho na matla a khohlano a thibelang motsamao oa boloko A. Matla a tsamaisang sistimi ea boloko ke boima ba boloko B.
Bala ho potlaka ha sistimi:
Bala matla a kgatello ya thapo (T):
Nahana ka motsamao oa e 'ngoe ea lintho, mohlala A. A e ea ka ho le letona.
Nka sebaka sa m A ho equation ea 1 ka m A ho equation ea 2.
Karabo e nepahetseng ke E.
10. Boloko bo boima ba 10 kg bo bewa fatshe le bataletseng ebe bo hulwa ke matla a rapameng F. Haeba coefficient ya static friction e le μs = 0,5 le coefficient ea kinetic friction μk = 0,3. Fumana boholo ba matla a khohlano ha boloko bo le mothating oa ho tsamaea. (g = 10 m/s2)
Puisano
Boloko bo tla tsamaya hantle haeba boholo ba matla a hulang = boholo ba matla a ho hohlana a sa fetoheng. Khohlano e sa fetoheng e sebetsa nthong (e thibela motsamao wa ntho) ha ntho e hulwa empa ntho e so tsamaye. Khohlano e sa fetoheng e na le boleng bo phahameng ha ntho e le mothating wa ho tsamaya (ntho ha e so tsamaye, ntho e batla e tsamaya). Ka lehlakoreng le leng, khohlano ya kinetic e sebetsa nthong (e thibela motsamao wa ntho) ha ntho e se e ntse e tsamaya.
Hoa tsebahala hore:
Potso: Matla a phahameng ka ho fetisisa a khohlano e sa fetoheng (f)s)?
Karabo:
Haeba ntho e le sebakeng se bataletseng joalo ka setšoantšong, boholo ba matla a tloaelehileng = boima ba ntho eo.
Matla a tloaelehileng (N) = matla a khoheli (w) = 100 Newtons
Foromo e phahameng ka ho fetisisa ea matla a khohlano e sa fetoheng:
Coefficient ea kinetic friction ha e sebelisoe lipalo.
11. Liboloko tse peli li hokahantsoe ka thapo e bobebe e huloang ke matla a rapameng F = 20 N (sheba setšoantšo). Haeba g = 10 ms-2 'me coefficient ea kinetic friction pakeng tsa block le bokaholimo ke 0,1, fumana boholo ba ho potlaka ha block...
Puisano
Hoa tsebahala hore:
E botsitsweng: ho potlakisa (a) ha boloko?
Karabo:
12. Boloko A bo nang le boima ba 2 kg le B bo nang le boima ba 4 kg di hlophisitswe jwalo ka ha ho bontshitswe setshwantshong. Haeba coefficient ya khohlano ya fatshe e feta coefficient ya khohlano ya boloko B ka makgetlo a mararo, boloko A bo tla tsamaya ka lebelo la 5 m/s.-2Kahoo karolelano ea matla a khohlano pakeng tsa boloko A le fatše ho liboloko A le B ke… g = 10 m/s2
Puisano
Hoa tsebahala hore:
O botsitse:
Papiso ea matla a khohlano a boloko A le fatše (f)s A) ka matla a khohlano a diboloko A le B (fs B)?
Karabo:
13. Sheba setshwantsho ka thoko! Boima ba boloko ka bong ke m.1 = 2 kg le m2 = 3 kg mme boima ba pulley bo hlokomolohuoa. Haeba bokaholimo ba sefofane bo boreleli mme g = 10 ms-2, ebe ho potlaka ha sistimi ke ....
A. 0,5 ms-2
B. 2,0 ms-2
C. 2,5 ms-2
D. 4,0 ms-2
E. 6,0 ms-2
Puisano
Hoa tsebahala hore:
m1 = 2 kg, m2 = 3 kg, g = 10 ms-2
w2 = m2 g = (3)(10) = 30 kg m/s2 kapa 30 Newtons
Potso: Ho potlaka ha sistimi (a)?
Karabo:
14. Ntho e nang le boima e hokahantsoe ka thapo e fetang ka har'a pulley e boreleli joalo ka ha ho bontšitsoe setšoantšong. Haeba m1 = 2 kg, m2 = 3 kg le g = 10 ms-2, joale boholo ba matla a khatello ea thapo T ke…
A. 10,2 N
B. 13,3 N
C. 15,5 N
D. 18,3 N
E. 24,0 N
Puisano
Hoa tsebahala hore:
m1 = 2 kg, m2 = 3 kg, g = 10 ms-2
w1 = (2)(10) = 20 Newton
w2 = (3)(10) = 30 Newton
Potso: Boholo ba matla a kgatello thapong (T) ke bofe?
Karabo:
w2 = 30 Newtons e kholo ho feta w1 = 20 Newtons ka hona m2 theohela tlase, m1 nyoloha.
Foromo ea molao oa bobeli oa Newton:
Matla a kgatello ya thapo?
Ho ya ka tataiso ya motsamao wa sistimi kapa tataiso ya ho potlakisa sistimi, tataiso ya matla a kgoheli m2 ho ya tlase, tataiso ya matla a kgatello ya thapo ho m2 ho ea holimo:
w2 - T2 = m2 a
30 – T2 = (3)(2)
30 – T2 = 6
T2 = 30 - 6
T2 = 24 Newton
Tataiso ea matla a khoheli m1 ho ya tlase, tataiso ya matla a kgatello ya thapo ho m1 ho ea holimo:
T1 - w1 = (m1) (a)
T1 – 20 = (2)(2)
T1 - 20 = 4
T1 = 4 + 20
T1 = 24 Newton
Matla a kgatello ya thapo (T) = T1 = T2 = 24 Li-Newton.
15. Liboloko tse peli, e 'ngoe le e 'ngoe e nang le boima ba 4 kg, li hokahantsoe ka thapo le pulley joalo ka ha ho bontšitsoe setšoantšong. Bokaholimo le pulley li boreleli. Haeba boloko B bo huloa ka matla a rapameng a 50 N, lebelo la boloko ke… (g = 10 m/s2)
A. 1,25 m/s2
B. 7,5 m/s2
C. 10 m/s2
D. 12,5 m/s2
E. 15 m/s2
Puisano
Hoa tsebahala hore:
mA = 4 kg, mB = 4 kg, g = 10 m/s2
wA = (mA)(g) = 4(10) = 40 Newton
F = 50 Newton
Ho botsoa: ho potlakisa sistimi?
Karabo:
Foromo ea molao oa bobeli oa Newton:
Ho potlaka ha diboloko ka bobedi ke 1,25 m/s2. Tsela eo diboloko tse pedi di tsamayang ka yona = tsela eo matla a ho kganna a tsamayang ka yona F.
16. Sheba setshwantsho ka thoko! Boima ba diboloko ke m 1 = 6 kg mme m 2 = 4 kg, mme boima ba pulley bo hlokomolohuwa. Haeba bokahodimo ba sefofane bo boreleli mme g = 10 ms −2 , jwale ho potlaka ha sistimi ke….
A. 0,5 ms-2
B. 2,0 ms-2
C. 2,5 ms-2
D. 4,0 ms-2
E. 5,0 ms-2
Puisano
Hoa tsebahala hore:
m1 = 6 kg, m2 = 4 kg, g = 10 m/s2
w1 = m1 g = (6 kg)(10 m/s2) = 60 kg m/s2 kapa 60 Newtons
w2 = m2 g = (4 kg)(10 m/s2) = 40 kg m/s2 kapa 40 Newtons
E botsitsweng: ho potlakisa sistimi (a)?
Karabo:
m1e holim'a bokaholimo bo boreleli, bo bataletseng bo se nang khohlano e le hore sistimi e tsamaiswe ke matla a khoheli boloko ba 2.
Terapkan Molao oa bobeli oa Newton :
∑F = ma
w2 = (m1 +m2) a
40 N = (6 kg + 4 kg) a
40 N = (10 kg) a
a = 40 N / 10 kg
a = 4 m/s2
Karabo e nepahetseng ke D.
17. Liboloko tse peli, e 'ngoe le e 'ngoe e nang le boima ba 2 kg, li hokahantsoe ka thapo le pulley joalo ka ha ho bontšitsoe setšoantšong. Bokaholimo le pulley li boreleli. Haeba boloko B bo huloa ka matla a rapameng a 40 N, lebelo la boloko ke… (g = 10 m/s 2 )
A. 5 m/s2
B. 7,5 m/s2
C. 10 m/s2
D. 12,5 m/s2
E. 15 m/s2
Puisano:
Hoa tsebahala hore:
mA = mB = 2 kg, g = 10 m/s2, F = 40 N
wA = mg = (2)(10) = 20 N
Potso: ho potlaka ha block (a)?
Karabo:
Bokaholimo ba boloko bo boreleli, ka hona matla a amang motsamao oa boloko ke feela matla F le boima ba boloko A.
Sebelisa molao oa bobeli oa Newton:
∑F = ma
F – wA = (mA +mB) a
40 – 20 = (2 + 2) a
20 = (4) a
a = 20/4
a = 5 m/s2
Karabo e nepahetseng ke A.
Sefofane se sekametseng
18. Boloko bo boima ba 2 kg bo le boemong bo boreleli bo sekametseng ka sekhutlo sa ho sekamela = 30o, e le hore boloko e tsamaye ka ho potlaka ho sa feleng. Haeba g = 10 ms-2, joale boholo ba matla a tsamaisang boloko ke...
A. 5 N
B. 6 N
C. 7 N
D. 8 N
E. 10 N
Puisano
Hoa tsebahala hore:
m = 2 kg, g = 10 m/s2, theta = 30o
w = mg = (2)(10) = 20 kg m/s2 = 20N
Potso: Ke matla afe a tsamaisang boloko?
Karabo:
Matla a tsamaisang boloko ke wx.
wx = w sin teta
wx = (20 N)(sebe 30o)
wx = (20 N)(0,5)
wx = 10 N.
Matla a tsamaisang boloko ke a 10 Newtons.
Karabo e nepahetseng ke E.
19. Liboloko tse peli li hokahantsoe ka thapo e bobebe e huloang ke matla a bataletseng F = 24 N. g = 10 ms-2 'me bokaholimo ba fatše bo thella. Boholo ba ho potlaka ha boloko ho sebelisoa molao oa bobeli oa Newton bakeng sa ntho ka 'ngoe ke...
Puisano
Hoa tsebahala hore:
m1 = 2 kg, m2 = 4 kg, F = 24 N
Potso: Ho potlaka ha block (a) ke eng?
Karabo:
Boholo ba lebelo la boloko ke 4 m/s2.
20. Ha o le ka lifting e sa sisinyeheng, boima ba Sandi ke 500 N. Ho potlaka ka lebaka la matla a khoheli = 10 ms-2Ha lifti e potlakisa, kgatello thapong e ba 750 N. Kahoo, ho potlakisa lifti ke...
A. 5,0 ms-2
B. 7,5 ms-2
C. 10,0 ms-2
D. 12,5 ms-2
E. 15,0 ms-2
Puisano
Hoa tsebahala hore:
w = 500 N, g = 10 m/s2, T = 750 N
Potso: ho potlaka ha lifti (a)?
Karabo:
Boima ba phasewete:
w = mg
500 = m (10)
m = 500 / 10
m = 50 kg
Boima ba lifti ha bo tsejoe kahoo boima bohle ba lifti le dikahare tsa yona = boima ba khoutu.
Ho ea ka molao oa pele oa Newton, haeba lifti e ntse e le teng, joale matla a hlahang = 0.
Matla a kgatello ya thapo (T) ha ho phahamiswa ho sa sisinyehe = 500 N.
Ha lifti e potlakisa, matla a khatello ea thapo (T) a fetoha 750 N kapa a eketseha ka 250 N.
Ho potlaka ha lifti ke 5 m/s2 'me tataiso ea ho potlaka = tataiso ea motsamao oa lifti e ea holimo.
Mohloli oa lipotso:
Lipotso tsa Fisiks tsa Tlhahlobo ea Naha bakeng sa Sekolo se Phahameng sa Thuto e Phahameng/Sekolo se Phahameng sa Mosebetsi
