1. E rua ngā papatipu m1 = 2 kg me te m2 = 5 kg kei runga i te papa whakarara, ā, e honoa ana mā te aho e whakaaturia ana i te pikitia. Ko te tauwehenga o te waku nekeneke i waenga i a m1 ā, ko te pikinga he 0.2, ā, ko te tauwehenga o te te waku nekeneke i waenganui i te m2 ā, ko te pikinga he 0.1.
(a) Whakatauhia ā rātou whakatere
(b) Whakatauhia te kaha kume

Mōhiotia:
Mass 1 (m1) = 2 kirokaramu
Taumaha 2 (m2) = 4 kirokaramu
Te tauwehenga o te waku nekeneke i waenga i te m1 a papa whakarara (μk1) = 0.2
Te tauwehenga o te waku nekeneke i waenga i te m2 me te papa whakarara (μ)k2) = 0.1
Whakaterenga na te kaha o te kaha (g) = 9.8 m/s2
a) Te rahi me te ahunga o te whakaterenga

w1 = taimaha 1 = m1 karamu = (2 kg)(9.8 m/s2) = 19.6 Niutona
w1x =w1 hara 30o = (19.6 N)(0.5) = 9.8 Nīutona
w1y =w1 whaimana 30o = (19.6 N)(0.87) = 17 Nīutona
N1 = Te kaha noa i runga i te m1 =w1y = 17 Niutona
Fk1 = Te kaha o te waku nekeneke i runga i te m1 = μk1 N1 = (0.2)(17 N) = 3.4 Nīhana
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w2 = taumaha 2 = m2 karamu = (4 kg)(9.8 m/s2) = 39.2 Niutona
w2x =w2 hara 60o = (39.2 N)(0.87) = 34.1 Nīutona
w2y =w2 whaimana 60o = (39.2 N)(0.5) = 19.6 Nīutona
N2 = Te kaha noa i runga i te m2 =w2y = 19.6 Niutona
Fk2 = Te kaha o te waku nekeneke i runga i te m2 = μk2 N2 = (0.1)(19.6 N) = 1.96 Nīhana
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Te rahi o te whakaterenga:
∑Fx = māx
w2x > w1x nō reira he rite tonu te ahunga o te whakaterenga ki te ahunga o w2x.
He pai ngā kaha e tohu ana i te ahunga whakaterenga, ā, he kino ngā kaha e tohu ana i te ahunga whakahāwea ki te whakaterenga.
w2x - Fk2 - T2 +T1 - w1x - Fk1 = (m1 +m2) ax
w2x - Fk2 - w1x - Fk1 = (m1 +m2 ) ax
34.1 N – 1.96 N – 9.8 N – 3.4 N = (2 kg + 4 kg) ax
18.94 N = (6 kg) ax
ax = 18.94 N : 6 kg
ax = 3.16m/s2
Te rahi o te whakaterenga = 3.16 m/s2 Te ahunga o te whakaterenga = te ahunga o T1 = te ahunga o te w2x
b) Te rahi o te kaha kume
Whakamahia te ture tuarua a Newton ki te mea 2:
w2x - Fk2 - T2 = m2 ax
34.1 N – 1.96 N – T2 = (4 kg)(3.16 m/s2)
32.14 N – T2 = 12.64 N
T2 = 32.14 N – 12.64 N = 19.5 Ngā Newton
Te kaha kume = T = T1 =T2 = 19.5 Niutona
2. m1 = 4 kg, mita2 = 2 kg. Whakatauhia (a) te rahi me te ahunga o te whakaterenga (b) Te rahi o te kaha kume e hono ana i a m1 me te m2 (c) te rahi o te kaha kume e hono ana i te pūrei me te tuanui.

otinga

w1 = m1 karamu = (4 kg)(9.8 m/s2) = 39.2 Niutona
w2 = m2 karamu = (2 kg)(9.8 m/s2) = 19.6 Niutona
a) Te rahi me te ahunga o te whakaterenga
∑Fy = māy
w1 > w2 nō reira he rite tonu te ahunga o te mea ki te ahunga o te taumaha 1 (w1)He pai ngā kaha he rite te ahunga ki te whakaterenga, ā, he kino ngā kaha he rite te ahunga ki te whakaterenga.
w1 - T1 +T2 - w2 = (m1 +m2) ay
w1 - w2 = (m1 +m2) ay
39.2 N – 19.6 N = (4 kg + 2 kg) ay
19.6 N = (6 kg) ay
ay = 19.6 N : 6 kg
ay = 3.26m/s2
Te rahi o te whakaterenga = 3.26 m/s2. Te ahunga o te whakaterenga = te ahunga o w1 .
b) Te rahi o te kaha kume e hono ana i a m1 me te m2
Anga Te ture tuarua a Newton i runga i te m2 :
∑Fy = māy
w1 - T1 = m1 ay
39.2 N – T1 = (4 kg)( 3.26 m/s2)
39.2 N – T1 = 13.04 N
T1 = 39.2 N – 13.04 N
T1 = 26.16 Niutona
Te rahi o te kaha kume e hono ana i ngā mea = T = T1 =T2 = 26.16 Niutona
c) Te rahi o te kaha kume e hono ana i te pūrakau me te tuanui.
Kei te okioki te pūrei:
∑Fy = māy —— hey = 0
∑Fy = 0
He pai ngā kaha whakarunga, he kino ngā kaha whakararo:
T3 - T1 - T2 = 0
T3 =T1 +T2
T1 a T2 he rite te rahi, T1 =T2 = T = 26.16 N :
T3 = 2T = 2(26.16 N) = 52.32 Ngā Niutona
3. Poraka 1 (m1 = 10 kg) me te poraka 2 (m2 = 15 kg) i honoa mā te taura i runga i te pūrei kore-waku. Te tauwehenga o te waku pūmau i waenga i te poraka 2 me te pikinga = 0.6. Ko te tauwehenga o te waku nekeneke i waenga i te poraka 2 me te pikinga = 0.42. Whakatauhia (a) Te rahi o te kaha iti rawa F i pā ki ngā mea kia tere ake ai ngā mea ki runga (b) Whakatauhia te rahi o te kaha kume.

otinga

w1 = Te taumaha o te poraka 1 = m1 karamu = (10 kg)(9.8 m/s2) = 98 Niutona
w2 = Te taumaha o te poraka 2 = m2 karamu = (15 kg)(9.8 m/s2) = 147 Niutona
w2y =w2 whaimana 30o = (147 N)(0.87) = 127.89 Nīutona
w2x =w2 hara 30o = (147 N)(0.5) = 73.5 Nīutona
N2 = Te kaha noa i runga i te poraka 2 = w2y = 127.89 Niutona
Fk2 = Te kaha o te waku nekeneke i runga i te poraka 2 = μk2 N2 = (0.42)(127.89 N) = 53.7 Nīhana
Fs2 = Te kaha o te waku pumau i runga i te poraka 2 = μs2 N2 = (0.6)(127.89 N) = 76.7 Nīhana
a) Te rahi o te kaha iti rawa F i pā ki ngā mea kia tere ake ai ngā mea ki runga
∑Fx = māx —— hex = 0
∑Fx = 0
He pai ngā kaha whakarunga me ngā kaha whakarunga matau, he kino ngā kaha whakararo me ngā kaha whakarunga maui.
Wh – Whk2 - w2x - w1 - T2 +T1 = 0
Wh – Whk2 - w2x - w1 = 0
F = Fk2 + w2x + w1
F = 53.7 N + 73.5 N + 98 N
F = 225.2 Newton
b) Te rahi o te kaha kume
Whakamahia te ture nekehanga a Newton ki te poraka 1:
∑Fy = māy —— hey = 0
∑Fy = 0
T1 - w1 = 0
T1 =w1 = 98 Niutona
Whakamahia te ture nekehanga a Newton ki te poraka 2:
Wh – Whk2 - w2x - T2 = 0
T2 = F – Fk2 - w2x
T2 = 225.2 N – 53.7 N – 73.5 N
T2 = 98 Niutona
Te rahi o te kaha kume = T1 =T2 = T = 98 Niutona
4. Poraka 1 (m1 = 16 kg) kei runga i te mata whakapae, ā, ko te poraka 2 (m2 = 12 kg) kei runga i tētahi papa whakarara maeneene, e honoa ana e tētahi taura e whiti ana i runga i tētahi porotiti iti, kore-waku. Poraka 3 (m3 = 5 kg) kei runga i te poraka 2. Ko te tauwehenga o te waku nekeneke i waenga i te poraka 2 me te mata whakapae he 0,4. Ko te coefKo te uara o te waku pateko i waenga i te poraka 2 me te poraka 3 he 0,3.
(a) Ina tukuna te pūnaha mai i te okiokinga, ka paheke tahi tonu te poraka 3 me te poraka 2?
(B) Mena kei reira te poraka 3, he aha te whakaterenga o te poraka 1 me te poraka 2?

Rongoā:
a) Ina tukuna te pūnaha mai i te okiokinga, ka paheke tahi tonu te poraka 3 me te poraka 2?

w1 = Te te taumaha o te poraka 1 = m1 karamu = (16 kg)(9.8 m/s2) = 156.8 Niutona
w1x =w1 hara 60o = (156.8 N)(0.87) = 136.4 Nīutona
w1y =w1 whaimana 60o = (156.8 N)(0.5) = 78.4 Nīutona
N1 = Te te kaha noa i pā ki te poraka 1 e te papa whakarara =w1y = 78.4 Niutona
w3 = Te te taumaha o te poraka 3 = m3 karamu = (5 kg)(9.8 m/s2) = 49 Niutona
N23 = Te te kaha noa i pā ki te poraka 3 e te poraka 2 =w3 = 49 Niutona
N32 = Te nte kaha noa i pā ki te poraka 2 e te poraka 3 = N23 =w3 = 49 Niutona
(N23 a N32 he takirua mahi-tauhohenga)
Fs23 = Te te kaha o te waku pao i pā ki te poraka 3 e te poraka 2 = μs N23 = (0.3)(49 N) = 14.7 Newton
Fs32 = Te te kaha o te waku pumau i pā ki te poraka 2 e te poraka 3 =Fs23 = 14.7 Niutona
(Fs23 a Fs32 he takirua mahi-tauhohenga)
w2 = Te te taumaha o te poraka 2 = m2 karamu = (12 kg)(9.8 m/s2) = 117.6 Niutona
N2 = Te te kaha noa i pā ki te mea 2 e te mata whakapae =w2 +N32 = 117.6 Ngā Newton + 49
Niutoni = 166.6 Niutoni
Fk2 = Te te kaha o te waku nekeneke i runga i te poraka 2 = μk N2 = (0.4)(166.6 N) = 66.64 Nīhana
Whakamahia te ture nekehanga a Newton ki te poraka 3:
∑Fx = māx
Fs23 =m3 ax
—–> Fs23 = μs N23 = μs w3 = μs m3 g
μs m3 g = m3 ax
μs g = ax
ax = (0.3)(9.8 m/s2) = 2.94 m/s2
Ko te whakaterenga mōrahi o te poraka 3 kia paheke tonu ai te poraka 3 me te poraka 2 ko 2.94 m/s2.
Nā, ka tatauhia e tātou te rahi o te whakaterenga o te pūnaha i muri i te tukunga mai i te okiokinga.
Ko te ahunga o te nekehanga o te poraka = te ahunga o te whakaterenga o te poraka = te ahunga o T2 = te ahunga o w1x.
∑Fx = māx
w1x - T1 +T2 - Fk2 - Fs32 +Fs23 = (m1 +m2 +m3) ax
w1x - Fk2 = (m1 +m2 +m3 ) ax
136.4 N – 66.64 N = (16 kg + 12 kg + 5 kg) ax
69.76 N = (33 kg) ax
ax = 2.11m/s2
ax he pai, ko te tikanga he rite te ahunga o te nekehanga poraka, te ahunga rānei o te whakaterenga ki te ahunga o T2 te ahunga rānei o w1x.
Ko te rahi o te whakaterenga ko 2.11 m / s2 , lnui atu i 2.94 m / s2 Nō reira, ka taea e tātou te whakatau ka paheke tahi tonu te poraka 3 me te poraka 2 i muri i te tukunga i te okiokinga.
b) Te rahi o te whakaterenga o te poraka 1 me te poraka 2
∑Fx = māx
w1x - Fk2 = (m1 +m2) ax
—–> Fk2 = μk N2 = μk w2 = μk m2 karamu = (0.4)(12 kg)(9.8 m/s2) = 47.04 Niutona
136.4 N – 47.04 N = (16 kg + 12 kg) ax
89.36 N = (28 kg) ax
ax = 89.36 N : 28 kg = 3.19 m/s2
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- Papatipu me te taumaha
- Te kaha noa
- Te ture tuarua o te nekehanga a Newton
- Te kaha waku
- Te nekehanga i runga i te mata whakapae me te kore he kaha waku
- Te nekehanga o ngā tinana e rua me te tere tere ōrite i runga i te mata whakapae taratara me te kaha waku
- Te nekehanga i runga i te papa whakarara me te kore he kaha waku
- Te nekehanga i runga i te papa whakarara taratara me te kaha waku
- Te nekehanga i roto i te ararewa
- Ka honoa te nekehanga o ngā tinana e ngā taura me ngā pūrere
- E rua ngā tinana he rite te rahi o te whakaterenga
- Te whakaawhiwhi i tētahi piko papatahi – ngā nekehanga porowhita
- Te whakaawhiwhi i tētahi kōpiko peeke – ngā hihiri o te nekehanga porowhita
- Te nekehanga ōrite i roto i te porowhita whakapae
- Te kaha pokapū i roto i te nekehanga porowhita ōrite
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