1. Koloi ea boima ba lik'hilograma tse 5000 e potlakile ho tloha phomolong ho ea ho 20 m/s. Fumana mosebetsi oa letlooa o entsoeng koloing.
Tse tsejoang:
Boima (m) = 5000 kg
Lebelo la pele (vo o ) = 0 m/s ( phomolo ea koloi )
Lebelo la ho qetela (v t ) = 20 m/s
Ho batloa : netweke
Tharollo:
Molao-motheo oa matla a kinetic a mosebetsi :
W net = Δ EK
Letlooa = ½ m (v t 2 – v o 2 )
W net = mosebetsi oa net
Δ EK = phetoho ea matla a kinetic
m = boima (kg),
v t = lebelo la ho qetela (m/s),
v o = lebelo la pele (m/s).
Marang-rang:
Letlooa = ½ m (v t 2 – v o 2 )
W nete = ½ (5000)(20 2 – 0 2 )
W letlooa = (2500)(400 - 0)
W letlooa = (2500)(400)
W net = 1000,000 Joule
[irp]
2. Ntho e boima ba 10-kg e potlakisitsoeng ho tloha ho 5 m/s ho isa ho 10 m/s. Fumana mosebetsi o entsoeng ka letlooa holim'a ntho eo!
Tse tsejoang:
Boima (m) = 10 kg
Lebelo la pele (v o ) = 5 m/s
Lebelo la ho qetela (v t ) = 10 m/s
Ho batloa : netweke
Tharollo:
Marang-rang:
W net = Δ EK
Letlooa = ½ m (v t 2 – v o 2 )
W nete = ½ (10)(10 2 – 5 2 )
W letlooa = (5)(100 - 25)
W letlooa = (5)(75)
W net = 375 Joule
3. Koloi e boima ba 2000 kg e theoha ka lebelo ho tloha ho 10 m/s ho isa ho 5 m/s. Mosebetsi o etswang koloing ke ofe?
Tse tsejoang:
Boima ba koloi (m) = 2000 kg
Lebelo la pele (v o ) = 10 m/s
Lebelo la ho qetela (v t ) = 5 m/s
Ho batloa: netweke
Tharollo:
Marang-rang:
W net = Δ EK
Letlooa = ½ m (v t 2 – v o 2 )
W nete = ½ (2000)(5 2 – 10 2 )
W letlooa = (1000)(25 - 100)
W net = (1000)(-75)
W net = -75,000 Joule
Letšoao la ho tlosa le bontša hore tataiso ea ho falla e fapane le tataiso ea matla a letlooa.
4. Matla a sa fetoheng a 60-N a sebediswang nthong ya boima ba 10-kg ka metsotswana e 12. Lebelo la pele la ntho ke 6 m/s mme tataiso ya ntho e tshwana le tataiso ya matla.
(1) Mosebetsi o entsoeng nthong eo ke 30,240 Joules
(2) Matla a ho qetela a kinetic ke li-joule tse 30,240
(3) Matla ke 2,520 Watt
(4) Keketseho ea matla a kinetic a ntho ke 180 Joules
Lipolelo tse nepahetseng ke…
Tse tsejoang:
Matla (F) = 60 N
Nako ea ho arohana (t) = metsotsoana e 12
Boima ba ntho (m) = 10 kg
Lebelo la pele (vo o ) = 6 m/s
Ho batloa: Lipolelo tse nepahetseng
Tharollo:
Ho potlakisa ntho:
∑F = ma
60 = 10 a
a = 60 / 10 = 6 m/s 2
Lebelo la ho qetela:
v t = v o + ho
v t = 6 + (6)(12)
v t = 6 + 72
v t = 78 m/s
Sebaka se tsamailoeng ka metsotsoana e 12:
s = vo o t + 1/2 ho 2
s = (6)(12) + 1/2 (6)(12) 2
s = 72 + (3)(144)
s = 72 + 432
s = limithara tse 504
(1) Mosebetsi o etsoang ka likhoka
W = F s = (60)(504) = 30,240 Joule
(2) Matla a ho qetela a kinetic
KE = 1/2 mv t 2 = 1/2 (10) (78) 2 = (5) (6084) = 30,420 Joules
(3) Matla
P = W / t = 30,240 / 12 = 2,520 Joules/motsotsoana
(4) Keketseho ea matla a kinetic
ΔKE = 1/2 mv t 2 – 1/2 mv o 2 = 1/2 m (v t 2 – v o 2 ) = 1/2 (10) (78 2 – 6 2 ) = 5 (6084 –36) = 5 (6048)
ΔKE = 30,240 Joule
[irp]
5. Mosebetsi o moholo o etsoa ka nomoro ea ntho…
Tharollo:
Mosebetsi oa netweke = phetoho ea matla a kinetic
Letlooa = ½ m (v t 2 – v o 2 )
Mosebetsi o moholo:
W 1 = ½ (8)(4 2 – 2 2 ) = (4)(16 – 4) = (4)(12) = 48 Dijoule
W 2 = ½ (8)(5 2 –3 2 ) = (4)(25 – 9) = (4)(16) = 64 Joule
W 3 = ½ (10)(6 2 – 5 2 ) = (5)(36 – 25) = (5)(11) = 55 Dijoule
W 4 = ½ (10)(4 2 – 0 2 ) = (5)(16 – 0) = (5)(16) = 80 Dijoule
W 5 = ½ (20)(3 2 – 3 2 ) = (10)(9 – 9) = (10)(0) = 0 Dijoule
6. Koloi ea boima ba 4000 kg e tsamaea moleng o otlolohileng ka lebelo la 25 m/s. Koloi e fokotsoa hore lebelo la ho qetela la koloi e be 15 m/s. Mosebetsi o etsoang koloing ke ofe?
Tse tsejoang:
Boima (m) = 4000 kg
Lebelo la pele (vo o ) = 25 m/s
Lebelo la ho qetela (v t ) = 15 m/s
Ho batloa : Mosebetsi o entsoeng koloing
Tharollo:
W net = ½ m (v t 2 – vo 2 ) = ½(4000)(15 2 -25 2 ) = (2000)(225-625) = (2000)(-400) = -800,000 Lijoule = -800 kJ
[irp]
7. 0.1-kg e lahleloang ka ho otloloha ho 6 m/s ho tloha bophahamong ba limithara tse 5. Haeba ho potlaka ha matla a khoheli e le 10 m/s 2 , joale matla a kinetic a bolo bophahamong ba limithara tse 2 ke afe.
Tse tsejoang:
Boima (m) = 0.1 kg
Phetoho ea bophahamo (h) = 5 m - 2 m = 3 metres
Ho potlaka ka lebaka la matla a khoheli (g) = 10 m/s 2
Ho batloa: Matla a kinetic a bophahamo ba limithara tse 2.
Tharollo:
Motsamao o otlolohileng o ka utloisisoa ka ho sekaseka likarolo tse otlolohileng le tse otlolohileng tsa motsamao ka thoko. Motsamao o shebileng ka ho rapama o sekasekoa e le motsamao o sa fetoheng oa lebelo le motsamao o shebileng ka ho rapama o sekasekoa e le motsamao oa ho oa ka bolokolohi kapa motsamao o otlolohileng.
Matla a pele a mechini = matla a khoheli a ka bang teng.
PE = mgh = (0.1)(10)(3) = 3 Joule.
Matla a ho qetela a mechini = matla a kinetic.
KE = 3 Joule.
8. Koloi ea boima ba lik'hilograma tse 1000 e potlakisa ho tloha phomolong 'me e tsamaea ka lebelo la 5 m/s. Mosebetsi o etsoang ke koloi ke ofe?
Tse tsejoang:
Boima (m) = 1000 kg
Lebelo la pele (v o ) = 0
Lebelo la ho qetela (v t ) = 5 m/s
Ho batloa: Mosebetsi (W) o etsoang ka koloi
Tharollo:
Letlooa = ½ m (v t 2 – v o 2 )
Mosebetsi o etsoang ka koloi:
W net = ½ (1000)(5 2 – 0 2 ) = (500)(25 – 0) = (500)(25) = 12,500 Joule
[irp]
9. Bolo ea ligrama tse 500 e lahleloa holimo holimo ho tloha holim'a lefatše ka lebelo la pele la 10 m/s 2 . Ho potlaka ka lebaka la matla a khoheli ke 10 ms -2 . Mosebetsi o etsoang ke matla a boima ke ofe ha bolo e fihla bophahamong bo phahameng ka ho fetisisa?
Tse tsejoang :
Boima ba bolo (m) = 500 grams = 0.5 kg
Lebelo la pele (v o ) = 10 m/s 2
Lebelo la ho qetela (v t ) = 0 (lebelo ntlheng e phahameng ka ho fetisisa)
Ho potlaka ka lebaka la matla a khoheli (g) = 10 m/s 2
Ho batloa: Mosebetsi (W) o etsoa ka boima
Tharollo:
Mosebetsi oa letlooa o etsoang ke matla a letlooa nthong = phetoho ea matla a kinetic.
W net = ΔEK = EK t – EK o
Letlooa = ½ mv t 2 – ½ mv o 2 = ½ m (v t 2 – v o 2 )
KE t = matla a ho qetela a kinetic, KE o = matla a pele a kinetic, m = boima ba ntho, v t = lebelo la ho qetela la ntho, v o = lebelo la pele la ntho.
Marang-rang:
W nete = ½ m (v t 2 – v o 2 ) = ½ (0.5)(0 2 – 10 2 )
W net = (0.25)(-100) = -25 Joule
Letšoao la ho tlosa le bontša hore tsela eo bolo e tsamaeang ka eona e fapane le boima ba eona. Tsela eo bolo e tsamaeang ka eona e otlolohile 'me tsela eo boima bo tsamaeang ka eona e otlolohile.
10. Ntho e boima ba 1-kg e oa ka bolokolohi ka phapang ea bophahamo = limithara tse 2.5. Ho potlaka ka lebaka la matla a khoheli ke 10 ms -2 . Mosebetsi o etsoang nthong eo ke ofe?
Tse tsejoang:
Boima ba bolo (m) = 1 kg
Lebelo la pele (vo o ) = 0 m/s
Bophahamo (h) = limithara tse 2.5
Ho potlaka ka lebaka la matla a khoheli (g) = 10 m/s 2
Ho batloa: Mosebetsi oa inthanete nakong ea ho falla
Tharollo:
Lebelo la ho qetela la bolo (v t )
Ho baloa ho sebelisoa equation ea motsamao oa ho oa ka bolokolohi. Tse tsejoang: Ho potlaka ka lebaka la matla a khoheli (g) = 10 m/s 2 , Phetoho ea bophahamo ba bolo (h) = limithara tse 2.5. Ho batloa: Lebelo la ho qetela.
v t 2 = 2 gh = 2(10)(2.5) = 2(25)
v t = √2(25)
v t = 5√2
Mosebetsi oa netweke = phetoho ea matla a kinetic
W nete = ΔEK = ½ m (v t 2 – v o 2 ) = ½ (1){(5√2) 2 – 0 2 }
W net = ½ (25)(2) = 25 Joule
[irp]
11. Ntho e boima ba 2 kg e tsamaya ka lebelo la 72 km/hora. Kamora ho tsamaya dimithara tse 400, lebelo la ho qetela la ntho ke 144 km/hora. Ho potlaka ka lebaka la matla a khoheli ke 10 ms -2 . Fumana mosebetsi wa netweke.
Tse tsejoang:
Boima ba ntho (m) = 2 kg
Lebelo la pele (v o ) = 72 km/hora = 20 m/s
Lebelo la ho qetela (v t ) = 144 km/h = 40 m/s
Sebaka (li) = limithara tse 400
Ho potlaka ka lebaka la matla a khoheli (g) = 10 m/s 2
Ho batloa: Marang-rang
Tharollo:
Mosebetsi oa netweke = liphetoho tsa matla a kinetic
W nete = ΔEK = ½ m (v t 2 – v o 2 ) = ½ (2) (40 2 – 20 2 }
W net = ½ (2)(1600 - 400) = 1200 Joule
12. Ntho e boima ba 2-kg e tsamaya ka 2 ms –1 . Mosebetsi o etswang nthong ke 21 Joules. Lebelo la ho qetela la ntho ke lefe.
Tse tsejoang:
Boima (m) = 2 kg
Lebelo la pele (vo o ) = 2 m/s
Mosebetsi (W) = 21 Joule
Ho batloa: lebelo la ho qetela (v t )
Tharollo:
W net = ΔEK
W net = 1/2 mv t 2 -1/2 mv o 2
Letlooa = 1/2 m (v t 2 – v o 2 )
21 = 1/2 (2) (v t 2 – 2 2 )
21 = (v t 2 – 2 2 )
21 = v t 2 – 4
v t 2 = 21 + 4 = 25
v t = √25
v t = 5 m/s
[irp]
1 3. Matla a sa fetoheng a 8 N a sebetsa nthong e boima ba 16 kg. Haeba ntho e phomotse qalong, joale fumana lebelo la ntho ka mor'a hore matla a sebetse nthong metsotsoana e 4.
Tse tsejoang:
Matla a sa fetoheng (F) = 8 Newton
Boima ba ntho (m) = 16 kg
Lebelo la pele la ntho (vo o ) = 0 m/s
Nako ea nako ea matla e sebetsa nthong (t) = metsotsoana e 4
Ho batloa: Lebelo la ho qetela (v t )
Tharollo:
Mosebetsi = Phetoho ea matla a kinetic
W = KE ea ho qetela – KE ea pele
W = ½ mv t 2 – ½ mv o 2
W = ½ mv t 2 – 0
W = ½ mv t 2 —— Tekanyo 1
Mosebetsi = Matla x Ho falla
W = F d
W = 8 d
Sebelisa equation ea motsamao o sa lekanang oa mola o ka tlase ho bala ho falla (d):
d = vo o t + ½ ho 2
d = ho falla, v o = lebelo la pele, t = nako e sa fellang, a = ho potlaka
d = 0 + ½ ho 2 = ½ ho 2 —-> a = (v t – vo o ) / t = v t / t
d = ½ (v t / t) t 2
d = ½ (v t ) t
Phetoho ea ho falla (d) ho equation ea Sebetsa le ho falla (d) ho equation ena:
W = 8 d
W = 8(1/2)(v t )(t)
W = (4)(v t )(t) —— equation 2
Tekanyo ea 1 = Tekanyo ea 2
W = W
½ mv t 2 = (4)(v t )(t)
½ mv t = (4)(t)
½ (16)(v t ) = 4(4)
8 v t = 16
v t = 16 / 8
v t = limithara tse 2/motsotsoana
14. Ho eketsa lebelo la ntho e fetohang makhetlo a 2 ho feta lebelo la pele, fumana mosebetsi o hlokahalang ts'ebetsong…
Tse tsejoang:
Boima ba ntho (m) = 1 kg
Lebelo la pele (vo o ) = 1 m/s
Lebelo la ho qetela (v t ) = 2 x lebelo la pele = 2 x 1 = 2 m/s
Ho batloa: Mosebetsi
Tharollo:
Matla a pele a kinetic:
KE qalong = ½ mv o 2 = ½ (1) (1) 2 = ½ (1) (1) = ½ (1) = 0.5
Matla a ho qetela a kinetic ha lebelo la ntho le fetoha makhetlo a 2 a lebelo la eona la pele:
HO ea ho qetela = ½ mv t 2 = ½ (1)(2) 2 = ½ (4) = 2
Khopolo-taba ea matla a sebetsang le a kinetic:
Mosebetsi = Phetoho ea matla a kinetic
Mosebetsi = Matla a ho qetela a kinetic – matla a pele a kinetic
Mosebetsi = 2 – 0.5
Mosebetsi = 1.5
Matla a kinetic a pele = 0.5
Mosebetsi = 3 x 0.5 = 1.5
Mosebetsi o hlokahalang ka makhetlo a 3 a matla a eona a kinetic a pele.
15. Koloi e boima ba 1500 kg e tsamaya ka lebelo la 36 km/hora tseleng e otlolohileng le e boreleli e otlolohileng. Koloi e potlakile ho fihla ho 72 km/hora. Fumana mosebetsi o hlokahalang ho potlakisa koloi.
Tse tsejoang:
Boima ba koloi (m) = 1500 kg
Lebelo la pele la koloi (v o ) = 36 km/hora = 36,000 metres / 3600 metsotsoana = 10 metres/motsotsoana
Lebelo la ho qetela la koloi (v t ) = 72 km/hora = 72,000 metres / 3600 metsotsoana = 20 metres/motsotsoana
Ho batloa: Ho hlokahala mosebetsi ho potlakisa koloi
Tharollo:
Khopolo-taba ea matla a sebetsang le a kinetic:
W = EK final – EK initial
W = ½ mv t 2 – ½ mv o 2 = ½ m (v t 2 –v o 2 )
W = ½ (1500)(20 2 - 10 2 )
W = ½ (1500)(400 - 100)
W = ½ (1500)(300)
W = (1500)(150)
W = 225,000 Joule
16. Ntho e boima ba 2 kg e qala ka lebelo la 72 km. hora -1 . Kamora ho tsamaya tseleng e otlolohileng e otlolohileng ho fihlela ho 400 m, lebelo la ntho ke 144 km. hora -1 . Fumana kakaretso ea mosebetsi holim'a ntho eo.
Tse tsejoang:
Boima ba ntho (m) = 2 kg
Lebelo la pele (v o ) = 72 km/hora = limithara tse 72,000 / metsotsoana e 3600 = 20 m/s
Lebelo la ho qetela (v t ) = 144 km/hora = 144,000 metres / metsotsoana e 3600 = 40 m/s
Sebaka sa ntho = limithara tse 400
Ho batloa: Mosebetsi oa inthanete nthong eo
Tharollo:
Khopolo-taba ea matla a kinetic a mosebetsi e bolela hore mosebetsi oa netweke o sebetsa nthong ka tsela e tšoanang le phetoho ea matla a kinetic a ntho.
W net = HO ea ho qetela – HO ea qalong
W net = ½ mv t 2 – ½ mv o 2
Letlooa = ½ m (v t 2 – v o 2 )
W nete = ½ (2) (40 2 – 20 2 )
W letlooa = 1600 – 400
W net = 1200 Joule
Tlhaloso:
W = Mosebetsi, KE = matla a kinetic
Matla a kinetic
17. Kulo ea ligrama tse 10 e tsamaeang ka lebelo le sa fetoheng la 100 m/s. Matla a kinetic a kulo ke afe?
Tse tsejoang:
Boima ba kulo (m) = 10 grams = 10/1000 lik'hilograma = 1/100 lik'hilograma = 0.01 lik'hilograma
Lebelo la kulo (v) = limithara tse 100/motsotsoana
Ho batloa: Matla a kinetic
Tharollo:
KE = 1/2 mv 2
KE = 1/2 (0,01 kg)(100 m/s) 2
KE = 1/2 (0,01 kg)(10.000 m 2 /s 2 )
KE = (0,01 kg)(5000 m 2 /s 2 )
KE = 50 kg m 2 /s 2
KE = 50 Joule
[ID ea sephutheloana sa wpdm='1191′]
- Mosebetsi o etsoang ka mathata a matla le litharollo
- Mathata le litharollo tsa matla a kinetic a mosebetsi
- Mathata le litharollo tsa motheo oa matla a sebetsang le a mechini
- Mathata a matla a khoheli le litharollo
- Matla a ka bang teng a mathata le litharollo tsa selemo se tenyetsehang
- Mathata a motlakase le litharollo
- Tšebeliso ea paballo ea matla a mechini bakeng sa motsamao oa ho oa ka bolokolohi
- Tšebeliso ea paballo ea matla a mechini bakeng sa motsamao oa holimo le tlase motsamaong oa ho oa ka bolokolohi
- Tšebeliso ea paballo ea matla a mechini bakeng sa motsamao holim'a sekhutlo
- Tšebeliso ea paballo ea matla a mechini bakeng sa motsamao sefofaneng se sekametseng
- Tšebeliso ea paballo ea matla a mechini bakeng sa motsamao oa liqhomane
