Mehlala e 4 ea Lipotso tsa Matla a Bohareng
1. Ntho e boima ba digrama tse 200 e tlangwa thapong e bobebe ebe e potoloha ka ho otloloha ka lebelo le sa fetoheng la 5 rad s –1 , jwalo ka ha ho bontshitswe setshwantshong se latelang. Haeba bolelele ba thapo e le l = 60 cm, boholo ba matla a bohareng a sebetsang nthong ke…
A. 0,3 N
B. 0,6 N
C. 3 N
D. 6 N
E. 30 N
Puisano
Hoa tsebahala hore:
Boima ba ntho (m) = 200 dikgerama = 200/1000 kg = 2/10 kg = 0,2 kg
Lebelo la Angular (ω) = 5 radians/motsotsoana
Bolelele ba thapo = radius (r) ea tsela e chitja = 60 cm = 60/100 metres = 0,6 metres
Potso: Boholo ba matla a bohareng a sebetsang nthong ke….
Karabo:
Matla a bohareng ke matla a hlahang a etsang hore ntho e be le lebelo la bohareng. Foromo ea matla a bohareng ke:
∑ F = ma s
∑ F = mv 2 /r = m ω 2 r
Tlhaloso: ∑ F = matla a bohareng, m = boima ba ntho, v = lebelo la tangential, ω = lebelo la angular, r = radius ea tsela e chitja.
∑ F = m ω 2 r = (0,2)(5) 2 (0,6) = (0,2)(25)(0,6) = 3 Li-Newton
Karabo e nepahetseng ke C.
2. Seithuti se otlolla lejoe le tlamiloeng qetellong ea khoele. Lejoe le potoloha ka ho otloloha joalo ka ha ho bontšitsoe kaholimo. Haeba lebelo la ho potoloha ha lejoe le imena habeli, matla a bohareng a fetoha...
A. ea pele ka makhetlo a 6
B. makhetlo a 5 hape
C. Lekhetlo le le leng hape
D. makhetlo a 2 hape
E. ea pele ka makhetlo a 2
Puisano
Hoa tsebahala hore:
Boima ba lejoe = m
Lebelo la lejoe = v
Bolelele ba thapo = radius = r
Potso: Haeba lebelo le imenne habeli, matla a bohareng a fetoha...
Karabo:
Haeba lebelo le imenne habeli, joale matla a bohareng a fetoha:
Matla a bohareng a fetoha a pele ka makhetlo a mane.
Karabo e nepahetseng ke C.
3. Sekhutlo tseleng e bataletseng se etselitsoe ho tsamauoa ke koloi ka lebelo le phahameng ka ho fetisisa la 10 ms –1 . Khokahano e lekanang pakeng tsa mabili le tsela ke 0,5 mme radius ya sekhutlo sa tsela ke R m. Ebe boleng ba R ke…. (g = 10 ms –2 )
A. Limithara tse 7,5
B. Limithara tse 8,0
C. Limithara tse 10
D. Limithara tse 15
E. Limithara tse 20
Puisano
Hoa tsebahala hore:
Lebelo (v) = 10 m/s
Palo ea khohlano pakeng tsa thaere le tsela (μs ) = 0,5
Ho potlaka ka lebaka la matla a khoheli (g) = 10 m/s 2
Potso: Radius ea kobeho ea tsela (limithara tsa R)
Karabo:
Matla a le mong feela a hlahang a rapameng a sebetsang koloing ha e reteleha ke khohlano e sa fetoheng . Foromo ea khohlano e sa fetoheng ke:
4. Koloi e kganna e kobehile tseleng sebakeng sa M jwalo ka ha ho bontshitswe setshwantshong se ka tlase.
Palo e lekanang ea khohlano e sa fetoheng pakeng tsa mabili le tsela ke 0,4 (ho potlakisa matla a khoheli 10 m/s -2 ). Ho thibela koloi ho tsoa tseleng, lebelo le phahameng ka ho fetisisa le lumelloang ke…
A. √10 ms-1
B. 2 √ 10 ms -1
C. 4 √ 10 ms -1
D. 5 √ 10 ms -1
E. 6 √ 10 ms -1
Puisano
Hoa tsebahala hore:
Koefficient ea khohlano e sa fetoheng (μ s ) = 0,4
Ho potlaka ka lebaka la matla a khoheli (g) = 10 m/s 2
Radius ea kobeho (R) = limithara tse 40
E botsitsweng: lebelo le phahameng ka ho fetisisa (v)
Karabo:
Molao oa bobeli oa Newton oa motsamao ka motsamao o chitja o tšoanang
Lintlha :
ΣF = matla a bohareng = matla a hlahang = matla a felletseng, m = boima ba ntho, a s = ho potlakisa bohareng, v = lebelo le otlolohileng, R = radius ea kobeho
Matla a bohareng
Matla a bohareng ke matla a hlahang a lebisitsoeng bohareng ba tsela e chitja. Ha koloi e tsamaea ka selikalikoe, matla feela a lebisitsoeng bohareng ke khohlano e sa fetoheng, kahoo khohlano e sa fetoheng ke matla a bohareng.
Foromo ea matla a khohlano e sa fetoheng:
Lintlha :
μ s = coefficient ea khohlano e sa fetoheng, w = boima ba ntho, m = boima ba ntho, g = ho potlaka ka lebaka la matla a khoheli.
Bala lebelo le phahameng ka ho fetisisa (v):
Karabo e nepahetseng ke C.
Mohloli oa lipotso:
Lipotso tsa Fisiks tsa Tlhahlobo ea Naha bakeng sa Sekolo se Phahameng sa Thuto e Phahameng/Sekolo se Phahameng sa Mosebetsi
