Te Tātai o te Kaha Waku: Te Whakamārama, Ngā Momo, me Ngā Whakamahinga
He kaha tino nui te waku i roto i te ahupūngao me te oranga o ia rā. Ahakoa e kiia ana he arai, he mea nui te waku ki te whakahohe i te nekehanga me te whakahaere i te tere. Ka matapakihia e tēnei tuhinga te whakamāramatanga o te waku, ngā tātai e pā ana ki te waku, ngā momo waku, me ētahi o ōna whakamahinga i roto i ngā horopaki rerekē.
Te Mārama ki te Waku
Ko te waku he kaha e puta ana ina pa ana ngā mata e rua, ka neke tetahi ki tetahi, ina neke tetahi mata ki tetahi. Ka mahi tēnei kaha ki te taha o te nekehanga, te ia rānei ki te neke, ā, ka mahi hei aukati, hei whakamutu rānei i te nekehanga.
Ka puta te waku nā ngā hapa o te mata i te taumata moroiti. Ahakoa ngā mata he maeneene te āhua i te taumata makoropiko, he hapa, he āhua pōuri hoki e hono tahi ana ina pa ana, ka puta he kaha e ātete ana ki te nekehanga whanaunga.
Ngā Tātai Kaha Waku
E rua ngā momo matua o te waku ka matapakihia e tātou: ko te waku pūmau me te waku nekeneke. He rerekē ngā tātai mō ēnei momo waku e rua, ahakoa he tauwehenga waku me te kaha noa kei roto i ngā mea e rua.
1. Te Kaha Waku Pūmau
Ko te waku pumau te kaha me wikitoria hei whakaoho i te nekehanga i waenga i ngā mata e rua e pā ana. Ka whakamahia tēnei kaha hei pupuri i tētahi mea kia tū tonu e pā ana ki tētahi atu mata tae noa ki te wā e pāngia ai tētahi kaha nui hei whakaoho i te nekehanga.
Ko te tātai mō te kaha waku pūmau mōrahi (\( f_s \)) ko:
\[ f_s \leq \mu_s N \]
Kei hea:
– Ko te kaha waku pumau mōrahi te \( f_s \),
– Ko te tauwehenga o te waku pumau ko \( \mu_s \),
– Ko te kaha noa te \( N \), arā, te kaha e mahi poutū ana ki te mata pa.
2. Te Kaha Waku Kinetic
Ko te waku nekeneke te kaha e mahi ana ki te whakahē i te nekehanga whanaunga i waenga i ngā mata e rua e neke ana tetahi ki tetahi. He iti ake tēnei kaha i te kaha waku pūmau mōrahi.
Ko te tātai mō te kaha waku nekeneke (\( f_k \)) ko:
\[ f_k = \mu_k N \]
Kei hea:
– Ko te kaha waku nekeneke te \( f_k \),
– Ko te tauwehenga o te waku nekeneke te \( \mu_k \),
– Ko te kaha noa ko \( N \).
Tauwehenga o te Waku
Ko te tauwehenga waku (\( \mu \)) he tau kore-ahu e tohu ana i te āhua o te taunekeneke i waenga i ngā mata e rua. E rua ngā momo tauwehenga waku he mea nui ki te tātari i ngā kaha waku: ko te tauwehenga waku pumau (\( \mu_s \)) me te tauwehenga waku nekeneke (\( \mu_k \)).
– Ko te tauwehenga o te waku pateko (\( \mu_s \)) he nui ake i te tauwehenga o te waku nekeneke, nā te mea he nui ake te kaha e hiahiatia ana hei tīmata i te nekehanga i te pupuri i te nekehanga.
– He iti ake te tauwehenga o te waku nekeneke (\( \mu_k \)), e whakaatu ana he iti ake te kaha e hiahiatia ana hei pupuri i te nekehanga.
Ko te uara o te tauwehenga waku e whakawhirinaki ana ki te takirua rauemi e pa ana me ngā āhuatanga o te mata, pērā i te taratara me te haumākū.
Ngā Momo o te Kaha Waku
1. Te Kaha Waku Maroke
Ka puta te waku maroke i waenganui i ngā mata totoka e rua e pā ana, kāore he hinu whakahinuhinu. Ka taea te wehewehe i tēnei waku ki te waku tūmau me te waku nekeneke, e ai ki te whakamārama i mua.
2. Te Kaha Waku Makuku
Ka puta te waku mākū ina he wai, he hinu whakahinuhinu rānei kei waenganui i ngā mata totoka e rua. Ka taea e ngā hinu whakahinuhinu te whakaiti i te waku mā te whakakī i ngā hapa o te mata, me te ārai i te pa tika i waenganui i ngā mata. Ka hua ake tēnei he iti ake te waku ki te whakataurite ki te waku maroke.
3. Kāhua Waku Panuku
Ka puta te waku hurihuri ina hurihuri tetahi mea i runga i te mata. He iti ake te waku hurihuri i te waku nekeneke nā te mea he iti ake te horahanga pa i waenga i te mea me te mata. Ko tētahi tauira o te waku hurihuri ko te waku i waenga i ngā wira o te waka me te rori.
4. Te Kaha o te Waku o te Hau
Ko te waku hau, te ātete hau rānei, ko te kaha e mahi ana ki te aukati i te nekehanga o tētahi mea i roto i te hau. Ka whakawhirinaki tēnei kaha ki te tere, te āhua, me te mātotoru o te hau o te mea. Ko te tātai whānui mō te waku hau (\( F_d \)) ko:
\[ F_d = \frac{1}{2} \rho v^2 C_d A \]
Kei hea:
– Ko te kaha waku hau te \( F_d \),
– Ko te mātotoru o te hau te \( \rho \),
– Ko te tere o te mea ko \( v \),
– Ko te tauwehenga tōia te \( C_d \),
– Ko te horahanga whakawhiti-wāhanga o te mea e poutū ana ki te ahunga nekehanga o te \( A \).
Taupānga Kāhua Waku
1. Ngā Waka Motuka
He mea nui te waku i waenga i ngā potae o te waka me te rori mō te haumaru me te mahi. Mā tēnei waku ka taea e te waka te tere ake, te huri, me te mutu. Mā te hoahoa potae pai me ngā mata rori kounga teitei ka taea te whakapai ake i te waku me te whakaiti i te mōrearea o ngā aituā.
2. Taputapu Hākinakina
I roto i ngā hākinakina, ka taea e te waku te mahi hei painga, hei arai rānei. Hei tauira, me whai hu pai te waku a ngā kaitākaro whutupaoro kia kore ai e paheke i runga i te papa. I tetahi atu taha, me whai hu tika te waku a ngā kaioma hei whakarato i te kukume e ranea ana me te kore e whakararu i te tere.
3. Ngā Mīhini me ngā Tikanga
Ka taea e te waku i roto i ngā mīhini me ngā tikanga te whakaiti i te pai o te mahi, me te whakararuraru hoki. Ka whakamahia te hinu whakahinuhinu hei whakaiti i te waku i waenga i ngā wāhanga neke, hei whakanui ake i te roa o te ora me te pai o te mahi a te mīhini. Mā te hoahoa pai ka whakaarohia hoki te whakaiti i te waku hei whakapai ake i te mahi.
4. Pūnaha Pēki
Ko te waku te kaupapa matua o te pūnaha parai o te waka. Ina pēhia te pēra parai, ka puta te waku mai i ngā papa parai ki te kōpae, ki te pahu rānei, ka whakaroa, ka mutu hoki te waka. He mea nui te tauwehenga waku tika i waenga i ngā papa parai me te kōpae ki te whai huatanga o te pūnaha parai.
5. Whakamahinga o ia rā
He mea nui te waku i roto i te oranga o ia rā. Mai i te hikoi i runga i ngā mata pahekeheke ki te whakatuwhera i ngā taupoki pounamu kikī, ka āwhina te waku i a tātou ki te whakahaere me te whakahaere i ngā mea. Mā te mārama ki te whakahaere i te waku ka taea te whakapai ake i te haumaru me te whai huatanga o ngā mahi o ia rā.
Tauira o te Tātaitanga o te Kaha Waku
Tauira 1: Te Tatau i te Kaha Waku Pūmau
Me kī kei runga i te mata papatahi he pouaka he 10 kg te taumaha, ā, he tauwehenga waku pumau tōna \( \mu_s = 0.5 \). He aha te kaha waku pumau mōrahi ka taea te mahi ki runga i te pouaka?
Tuatahi, ka tatauhia e tātou te kaha noa (\( N \)):
\[ N = mg \]
\[ N = 10 \, \text{kg} \times 9.8 \, \text{m/s}^2 \]
\[ N = 98 \, \kuputuhi{N} \]
Kātahi ka whakamahia e mātou te tātai mō te kaha waku pūmau mōrahi:
\[ f_s \leq \mu_s N \]
\[ f_s \leq 0.5 \times 98 \, \text{N} \]
\[ f_s \leq 49 \, \text{N} \]
Nō reira, ko te kaha waku pūmau mōrahi ko 49 N.
Tauira 2: Te Tatau i te Kaha Waku Kinetic
Me kī, e neke ana tētahi pouaka he 10 kg te taumaha i runga i tētahi mata papatahi me te tauwehenga o te waku nekeneke \( \mu_k = 0.3 \). He aha te kaha o te waku nekeneke e pā ana ki te pouaka?
Tuatahi, ka tatauhia e tātou te kaha noa (\( N \)):
\[ N = mg \]
\[ N = 10 \, \text{kg} \times 9.8 \, \text{m/s}^2 \]
\[ N = 98 \, \kuputuhi{N} \]
Kātahi ka whakamahia e mātou te tātai mō te waku nekeneke:
\[ f_k = \mu_k N \]
\[ f_k = 0.3 \times 98 \, \text{N} \]
\[ f_k = 29.4 \, \kuputuhi{N} \]
Nō reira, ko te kaha waku nekeneke he 29.4 N.
Whakamutunga
He tino hira te kaha o te waku i roto i ngā āhuatanga maha o te ao me te hangarau. Mā te mārama ki te whakamāramatanga, te tauira, me ngā momo waku, ka taea e tātou te mārama ki te mahi a te waku.
Ka pā ki te nekehanga me te mahi i roto i ngā horopaki maha. Mai i ngā waka motuka ki ngā taputapu hākinakina, he mea nui te waku ki te pupuri i te taurite i waenga i te nekehanga me te whakahaere.
