Pūngao pūmanawa – ngā raruraru me ngā otinga

Pūngao pūmanawa – ngā raruraru me ngā otinga

Te pūngao pūngao tōkaha

1. Pūngao 4900 Joule e whakamahia ana hei whakaara i tētahi mea he 50 kg te taumaha ki te teitei o h. He aha te teitei o h? Whakaterenga na te kaha o te kaha (g) = 9.8 ms^-2.

Mōhiotia:

Tuhinga o mua te kaha haere (ΔPE) = 4900 Joule

Mass o te mea (m) = 50 kg

Te whakaterenga nā te kaha ā-papa (g) = 9.8 m/s²

Hiahia: teitei (Δh)

Rongoā:

ΔPE = mg Δh

4900 = (50)(9.8) Δh

4900 = 490 Δh

Δh = 10 mita

Pūngao pūmanawa o te puna

2. E whakaatu ana te kauwhata i raro nei i te whanaungatanga i waenga i te kaha (F) me te x (te huringa o te roa) o te puna. Mena he 8 cm te huringa o te roa o te puna, he aha te kaha pūmanawa o te puna?

Mōhiotia:

Te Kaha (F) = 2 Newton

Ko te panonitanga o te roa 1 (x) = 1 cm = 1/100 m = 0.01 m

Ko te panonitanga o te roa 2 = 8 cm = 8/100 m = 0.08 m

E hiahiatia ana: Te pūngao pūmanawa o te puna

Rongoā:

Te pūmau o te kōanga:

Te pūngao pūmanawa o te puna:

∆PE = 1/2 kx²

∆PE = 1/2 (200 N/m)(0.08 m)²

∆PE = (100 N/m)(0.0064 m)²)

∆PE = 0.64 Nm

3. E ai ki te ripanga i raro nei, F = te taumaha o te mea, ∆L = te huringa o te roa o te puna. He aha te mahi i mahia ki te puna, nō reira ko te huringa o te roa o te puna he 10 cm.

Mōhiotia:

Ko te panonitanga o te roa o te puna (∆L) = 10 cm = 0.1 m

E hiahiatia ana: Ngā mahi i mahia i te puna

Rongoā:

Te pūmau o te kōanga:

k = F / ∆x = 20 N / 0.04 m = 500 N/m

k = F / ∆x = 30 N / 0.06 m = 500 N/m

k = F / ∆x = 40 N / 0.08 m = 500 N/m

Ko te pūmau o te puna he 500 N/m

Ka oti te mahi i runga i te puna, nō reira ko te huringa o te roa o te puna he 10 cm:

W = 1/2 k ∆L² = 1/2 (500 N/m)(0.1 m)² = (250 N/m)(0.01 m)²) = 2.5 N m = 2.5 Joule.

4. E whakaatu ana te kauwhata i raro nei i te whanaungatanga i waenga i te kaha (F) me te huringa o te roa (x). He aha te pūngao pūmanawa o te puna i runga i te kauwhata i raro nei.

Mōhiotia:

F = 40 Newton

Δx = 0.08 m

E hiahiatia ana: pūngao pūmanawa o te puna

Rongoā:

Te pūmau o te kōanga:

k = F / Δx

Te pūngao pūmanawa o te puna:

PE = ½ k Δx² = ½ (F/Δx) Δx² = ½ F Δx

PE = ½ (40)(0.08) = (20)(0.08) = 1.6 Joules

1. He aha te pūngao pūmanawa?
   • WhakautuKo te pūngao pūmanawa ko te pūngao kei tētahi mea nā tōna tūranga, tōna āhua rānei. Koinei te pūngao he pūmanawa ki te mahi engari kāore e whakaoho i te nekehanga i tēnei wā.
2. He pēhea te pānga o te pūngao pūmanawa ā-papa ki te teitei?
   • WhakautuHe rite tonu te kaha pūmanawa ā-papa ki te teitei o tētahi mea i runga ake i tētahi pūwāhi tohutoro. Ko te tātai ko PE$=mgh$, ko PE te pūngao pūmanawa, $m$ he papatipu, $g$ ko te whakaterenga ā-papa, me $h$ ko te teitei.
3. He aha i kiia ai he pūngao pūmanawa tō te puna kua totorohia, kua pēhia rānei?
   • WhakautuIna totorohia, ina pēhia rānei te puna mai i tōna tūranga taurite, ka rongoa e ia te pūngao. Kei tēnei pūngao te pūmanawa ki te mahi i te wā e hoki ai te puna ki tōna āhua taurite. Ka kiia tēnei pūngao kua rongoatia ko te pūngao pūmanawa pīngore.
4. Me pēhea te rerekētanga o te pūngao pūmanawa o tētahi mea mēnā ka whakapikihia ki te rua o tōna teitei taketake i roto i te papa tōpana?
   • WhakautuKi te hikitia tētahi mea ki te rua o tōna teitei taketake, ka rua te kaha pūmanawa ā-papa. Nā te mea he whakawhirinaki raina te kaha pūmanawa ki te teitei.
5. E taea ana rānei te whai pūngao pūmanawa kino i tētahi mea? Whakamāramahia.
   • WhakautuĀe, ka taea e te pūngao pūmanawa te kino i runga i te tohutoro kua whiriwhiria. Hei tauira, i roto i ngā raruraru pūngao pūmanawa ā-papa, he maha ngā wā ka whakatakotoria e tātou te whenua he kore pūngao pūmanawa. Mena kei raro iho i tēnei tohutoro tētahi mea (pērā i roto i tētahi puna), ka kino tōna pūngao pūmanawa e pā ana ki te tohutoro kua whiriwhiria.
6. He aha te hononga o te pūngao pūmanawa ki te pūngao nekeneke i roto i tētahi pūnaha kati?
   • WhakautuI roto i tētahi pūnaha kati kāore he kaha o waho, ka noho pūmau tonu te pūngao katoa (kinikini + pūmanawa). Ko tēnei mātāpono e hangai ana ki te tiaki i te pūngao. I te pikinga ake o te pūngao pūmanawa, ka heke te pūngao kinikini, ā, ko te ritenga kē.
7. Ka ahatia te kaha pūmanawa ā-papa o te aporo ina taka mai i te rākau?
   • WhakautuI te hinganga o te aporo, ka heke tōna kaha pūmanawa ā-papa nā te mea kua tata atu ki te Ao. Ka hurihia tēnei kaha pūmanawa kua ngaro hei kaha nekeneke, ka tere ake te neke o te aporo i a ia e hinga ana.
8. He aha te take e nui rawa ai te pūngao pūmanawa o te pendulum i te tihi o tōna nekehanga?
   • WhakautuI te tihi o tōna piu, kei te tino teitei te pendulum e pā ana ki tōna tūranga okiokinga. Ko te tikanga kei a ia te teitei mōrahi, nō reira, te kaha pūmanawa ā-papa mōrahi. I a ia e piu ana ki raro, ka hurihia tēnei kaha ki te kaha nekeneke.
9. Ka taea e te mea te whai pūngao pūmanawa ahakoa kāore i roto i te papa ā-papa?
   • WhakautuĀe. Kāore te pūngao pūmanawa e motuhake ki ngā papa ā-papa. Hei tauira, he pūngao pūmanawa ngāwari tonu kei te puna kōpeke i runga i te teihana mokowhiti (he iti noa ngā pānga ā-papa). Waihoki, he pūngao pūmanawa hiko kei ngā utu i roto i te papa hiko.

10. He pēhea te awe o te papatipu o tētahi mea ki tōna pūngao pūmanawa ā-papatipu?

    • WhakautuHe rite tonu te kaha pūmanawa ā-papatipu ki te papatipu o tētahi mea. Mēnā ka takiruahia te papatipu o tētahi mea, ka takirua anō hoki tōna kaha pūmanawa ā-papatipu (i te teitei kotahi).