Ngā Tauira Pātai mō te Kaha Pokapū

4 Ngā Tauira o ngā Pātai mō te Kaha Pokapū

1. Ka herea tētahi mea he 200 karamu te taumaha ki tētahi taura māmā, kātahi ka hurihia whakapaetia ki tere koki e noho tonu ana i te 5 rad s^-1, pērā i te ahua e whai ake nei. Mena ko te roa o te taura ko l = 60 cm, ko te rahi o te kaha pokapū e pā ana ki te mea ko...

A. 0,3 N

B. 0,6 N

C. 3 N

D. 6 N

E. 30 N

Kōrero

E mōhiotia ana:

Taumaha o te mea (m) = 200 karamu = 200/1000 kg = 2/10 kg = 0,2 kg

Tere koki (ω) = 5 rātiana/hekona

Te roa o te taura = te pūtoro (r) o te ara porowhita = 60 cm = 60/100 mita = 0,6 mita

I pātaihia: Ko te rahi o te kaha pokapū e pā ana ki tētahi mea ko….

Whakautu:

Ko te kaha pūrua te kaha hua e meinga ai te mea kia pāngia e te whakaterenga pūrua. Ko te tātai mō te kaha pūrua ko:

∑F = ma_s

∑F = mv²/r = mω² r

Ngā Mōhiohio: ∑F = te kaha pokapū, m = te papatipu o te mea, v = te tere pātata, ω = te tere koki, r = te pūtoro o te ara porowhita.

∑F = mω² r = (0,2)(5)² (0,6) = (0,2)(25)(0,6) = 3 Ngā Niutona

Ko te whakautu tika ko C.

2. Ka takahurihia e te tauira tētahi kōhatu e herea ana ki te pito o te aho. Ka hurihia te kōhatu ki te taha whakapae e whakaaturia ana i runga ake nei. Mēnā ka takiruahia te tere o te hurihanga o te kōhatu, ka huri te kaha porowhita hei...

A. 6 ngā wā taketake

B. E rua ngā wā anō

C. 4 ngā wā taketake

D. 2 ngā wā anō

E. 2 ngā wā taketake

Kōrero

E mōhiotia ana:

Papatipu o te kōhatu = m

Tere o te kōhatu = v

Te roa o te taura = te pūtoro = r

I pātaihia: Ki te whakareatia te tere, ka huri te kaha pokapū hei…

Whakautu:

Ki te whakareatia te tere, ka noho te kaha porotītaha ki:

E whā ngā whakarea o te kaha pokapū i tōna kaha taketake.

Ko te whakautu tika ko C.

3. Kua hangaia he piko i runga i te rori papatahi kia taea ai e te motuka te haere i te tere mōrahi o te 10 m/s.^-1. E mōhiotia ana ko te tauwehenga o te waku i waenga i te potae me te rori he 0,5, ā, ko te radius o te piko o te rori he R m. Kātahi ko te uara o R ko…. (g = 10 ms^-2)

A. 7,5 mita

B. 8,0 mita

C. 10 mita

D. 15 mita

E. 20 mita

Kōrero

E mōhiotia ana:

Tere (v) = 10 m/s

Ko te tauwehenga o te waku i waenga i te potae me te rori (μ_s) = 0,5

Te whakaterenga nā te kaha ā-papa (g) = 10 m/s²

I pātaihia: Te whānui o te piko o te rori (R mita)

Whakautu:

Ko te kaha hua anake i te ahunga whakapae e pā ana ki te motuka ina tahuri te motuka ko te kaha waku pumauTe tātai kaha waku pūmau:

4. Kei te taraiwa te motuka i tētahi piko o te rori i te tūranga M e whakaatuhia ana i te pikitia i raro nei.

Ko te tauwehenga o te waku pao i waenga i te wira me te rori he 0,4 (whakaterenga ā-papa 10 ms^-2Hei ārai i te waka kei hē te ara, ko te tere mōrahi e whakaaetia ana ko…

A. √10 ms^-1

B. 2√10 ms^-1

C. 4√10 ms^-1

D. 5√10 ms^-1

E. 6√10 ms^-1

Kōrero

E mōhiotia ana:

Tauwehenga waku pumau (μ)_s) = 0,4

Te whakaterenga nā te kaha ā-papa (g) = 10 m/s²

Te whānui o te piko (R) = 40 mita

I pātaihia: tere mōrahi (v)

Whakautu:

Tātai Te ture tuarua a Newton I te nekehanga porowhita ōrite

Ngā Mōhiohio:

ΣF = te kaha pokapū = te kaha hua = te kaha katoa, m = te papatipu o te mea, a_s = whakaterenga pūrua, v = tere rārangi, R = pūtoro piko

Te kaha pokapū

Ko te kaha pūrua te kaha hua e anga ana ki waenganui o te ara porowhita. Ina neke te motuka i roto i te porowhita, ko te kaha anake e anga ana ki waenganui ko te waku pumau, nō reira he kaha pūrua te waku pumau.

Te tātai kaha waku pumau:

Ngā Mōhiohio:

μ_s = te tauwehenga o te waku pateko, w = te taumaha o te mea, m = te papatipu o te mea, g = te whakaterenga nā te kaha ā-papatipu.

Tātaihia te tere mōrahi (v):

Ko te whakautu tika ko C.

Pūtake pātai:

Ngā Pātai Ahupūngao Whakamātautau ā-Motu mō te Kura Tuarua/Kura Tuarua Mahi-ā-ringa