3 ngā pātai mō te whārite kaha noa
1. He 5 kg te taumaha o tētahi poraka. Mēnā ko te g = 10 m/s 2 , whakatauhia:
a) te taumaha o te poraka
b) te kaha noa mēnā ka whakatakotoria te poraka ki runga i te papa papatahi
c) te kaha noa mēnā ka tau te poraka ki runga i tētahi papa whakarara e hanga ana i tētahi koki 30 ° ki te whakapae
Mōhiotia:
Ko te taumaha o te poraka (m) = 5 kg
Te whakaterenga nā te kaha ā-papa (g) = 10 m/s 2
E hiahiatia ana: w, N i runga i te papa me N i runga i te pari
Rongoā:
a) Taumaha kurupae
w = mg = 5 (10) = 50 Newton
b) Te kaha noa mēnā kei roto te poraka i te papa papatahi
N = w = 50 Newton
c) Te kaha noa mēnā kei runga te poraka i tētahi papa whakarara
N = w y = w cos θ = 50 (cos 30) = 50 (½ √3) = 25√3 Newtons
2. E pēhia ana tētahi ūkui 120 karamu ki te papa me te kaha o te 15 N. He aha te kaha noa e pā ana ki te ūkui?
Kua mohiotia:
Taumaha (m) = 120 karamu = 0.12 kg
Te Kaha (F) = 15 Newton
E hiahiatia ana: Te kaha noa
Rongoā:
Te kaha noa = te pana = 15 Newton
3. Ka tōia te wai inu pounamu kei roto tonu i te pouaka ki te kaha o F = 200 N, ā, ka hanga he koki 37 o ki te taha whakapae. Sin 37 o = 0.6. Ko te taumaha o te kāri me ōna mea kei roto he 20 kg. Mena ko te tauwehenga o te waku pumau i runga i te papa he 0.5, ā, ko te tauwehenga o te waku nekeneke i runga i te papa he 0.2, tātaihia te kaha noa e pā ana ki te kāri.
Mōhiotia:
Te kaha tō (F) = 200 N
Hara 37 = 0,6
Fy = F hara 37 = (200)(0,6) = 120 N
Papatipu kāri (m) = 20 kg
Te taumaha o te kātene (w) = mg = (20)(10) = 200 N
E hiahiatia ana: Te kaha noa i runga i te kātene (N)
Rongoā:
Tātaihia te kaha noa mā te whakamahi i te tātai kaha noa:
N = w – F y = 200 – 120 = 80 Ngā Newton
