1. Te whakamāramatanga o te whakawhiti wera mā te irahiko
He aha te āhua o te kakahu pango i te rā wera, ā, i te wā rānei e whakakorikori tinana ana koe i te awatea? Whakatairitea ki te kakahu mā? Ki te kakahu pango koe i te awatea, ka wera koe. He aha ai? Ko te tawhiti i waenganui i te rā me te whenua i te ata he rite tonu ki te tawhiti i waenganui i te rā me te whenua i te awatea me te ahiahi. Nā, he aha i mātao ake ai, i wera ake ai ngā ata me ngā ahiahi i te awatea? Ko ngā whakautu ki ēnei pātai e pā ana ki te whakawhiti wera mā te irahiko.
Ko te whakawhiti wera mā te irahiko he whakawhiti wera i roto i te āhua o ngā ngaru hikohiko. Ko ngā tauira o te whakawhiti wera mā te irahiko ko te mahana o tō tinana ina tata koe ki te oumu me te whakawhiti wera mai i te rā ki te whenua. He teitei ake te pāmahana o te rā (tata ki te 6000 Kelvin), engari he iti iho te pāmahana o te whenua. Nā te rerekētanga pāmahana i waenga i te rā me te whenua ka neke te wera mai i te rā (he pāmahana teitei ake) ki te whenua (he pāmahana iti iho). Mena me whai takawaenga, he reo rānei te whakawhiti wera mai i te rā ki te whenua, pērā i te whakawhiti wera mā te kawe me te whakawhiti wera, kāore e taea e te wera te tae ki te whenua; me haere te wera mā te korehau (me te tata kore rānei). Ki te kore he wera mai i te rā, e kore rawa te ora i runga i te whenua nā te mea me whai pūngao mai i te rā te ora.
Ko tētahi atu tauira o te whakawhiti wera mā te hihi ko te wera e pā ana ki a tātou ina tata tātou ki te mura. Ehara te wera e pā ana ki a tātou i te mea nā te hau wera rawa i puta mai i te mura. E ai ki te whakamārama i mua ake nei, ka whānui te hau wera kia heke ai te mātotoru. Nō reira, ka neke poutū ake te hau he iti te mātotoru, kāore e neke whakapae ki a tātou. Ka mahana, ka wera rānei te tinana ina tata ki te mura nā te mea ka neke te wera mā te hihi mai i te mura (te pāmahana teitei ake) ki te tinana (te pāmahana iti iho).
He rerekē te whakawhiti wera mā te hihi i te whakawhiti wera mā te kawe me te kawe. Ka puta te whakawhiti wera mā te kawe me te kawe ina pā ngā mea he rerekē te pāmahana tetahi ki tetahi. I tetahi atu taha, ka taea te whakawhiti wera mā te hihi me te kore e pā.
2. Te whārite o te whakawhiti wera mā te irahiko
Ko te tere o te whakawhiti wera mā te hihi he rite ki te horahanga o te mea me te pāmahana tino (Te Tauine Kelvin) o te mea. Ko ngā mea he nui ake te horahanga o te mata, he nui ake te tere whakawhiti wera i ngā mea he iti ake te horahanga o te mata.
Waihoki, ko ngā mea he 2000 Kelvin te pāmahana, hei tauira, he 2 te tere whakawhiti wera.4 = 16 ngā wā nui ake i ngā mea he 1000 Kelvin te pāmahana. I kitea tēnei hua e Josef Stefan i te tau 1879, ā, i ahu mai i te ariā e Ludwig Boltzmann i te rima tau i muri mai.
Q = wera, t = wā, A = horahanga mata o te mea (m2), T = te pāmahana tino o te mea (K) e = te whakaputanga (te tau kore-ahu e rere ana te rahi mai i te 0 ki te 1), σ = 5.67 x 10-8 W / m2.K4 (Te pūmau whānui. E mōhiotia ana hoki ko te pūmau Stefan-Boltzmann), Q/t = te tere o te whakawhiti wera mā te irahiko
Ko ngā mea he mata pōuri (mangu) he tata ki te 1 te kaha whakaputanga o te hihi, ko ngā mea he tae mārama he tata ki te 0. Ko te nui ake o te kaha whakaputanga o te hihi o te mea (e tata ki te 1), ko te nui ake o te tere wera e tukuna ana e te mea. I tetahi atu taha, ko te iti ake o te kaha whakaputanga o te hihi o te mea (e tata ki te 0), ko te iti ake o te tere wera e tukuna ana. Ka taea e tātou te kī he nui ake te wera e tukuna ana e ngā mea pōuri (mangu) i ngā mea mārama (mā).
Ehara i te mea ko te nui o te kaha whakaputa wera anake te mea e whakatau ana i te kaha o tētahi mea ki te tuku wera, engari ko te kaha hoki o tētahi mea ki te mimiti i te wera e tukuna ana e ētahi atu mea. Ko ngā mea he kaha whakaputa wera tata ki te 1 (ngā mea pouri) ka mimiti i te nuinga o te wera e tukuna ana ki runga i a rātou. He iti noa te wāhanga e whakaatahia ana. I tetahi atu taha, ko ngā mea he kaha whakaputa wera tata ki te 0 (ngā mea mārama) ka mimiti i te iti o te wera e tukuna ana ki runga i a rātou. Ko te nuinga o te wera ka whakaatahia e te mea. Ko te mea e mimiti ana i te wera katoa e tukuna ana ki runga i a ia, ko tōna kaha whakaputa wera = 1. E mōhiotia ana tēnei momo mea ko te "mea mangu." Kāore te kupu mea mangu e whakamārama ana he mangu ngā mea, engari e whakamārama ana i te kaha o ngā mea ki te mimiti i te wera katoa e tukuna ana ki runga i a rātou.
3. Te tere o te wera e tukuna ana e te rā
I runga i ngā tātaitanga (e ai ki te ao tūturu), i kitea he wera 1350 Joule ia hekona ia mita tapawha i neke mai i te rā ki te whenua. I tētahi rā kanapa (kāore he kapua), he wera 1000 Joule ia hekona ia mita tapawha ka tae ki te mata o te whenua. I tētahi rā paki (he maha ngā kapua), tata ki te 70% o te wera ka mimitihia e te āhuarangi o te whenua, 30% anake o te wera ka tae ki te mata o te whenua. Ko te nui o te wera e ngaro ana i te āhuarangi o te whenua e whakawhirinaki ana ki te maha, ki te torutoru rānei o ngā kapua. Ko te nui o te wera 1350 Joule ia hekona ia mita tapawha e mōhiotia ana ko te pūmau rā. Nā te mea ko ngā Joule ia hekona (J/s) = Watts, kātahi ka taea e tātou te tuhi anō i te pūmau rā ki te 1350 Watts ia mita tapawha = 1350 W/m2
Ina tae te wera e tukuna ana e te rā ki te mata o te whenua, ka mimitihia te wera e te whenua me ngā mea kei runga i te mata o te whenua. Ko te tere mimiti wera e whakawhirinaki ana ki te kaha whakaputa wera (e) o te mea, te horahanga o te mata o te mea me te koki i hangaia e te rā me te rārangi poutū ki te mata o te mea.
mōhiohio:
Q/t = te tere mimiti wera, 1000 W/m2 = te pūmau o te rā, e = te kaha whakaputa o te mea, A = te horahanga o te mata o te mea, θ = te koki i hangaia e te hihi o te rā me ngā rārangi poutū ki te mata o te mea,
A cos θ = horahanga whai hua (te horahanga mata wāhanga o ngā mea e poutū ana ki te hihi o te rā)
I te awatea, ka whakarara, ka tutuki rānei ngā hihi o te rā ki tētahi rārangi poutū ki te mata o te whenua (koki i hangaia = 0).
Ko te raro i hangaia = 0o, nō reira, ko te tere mimiti wera ko:
Ko te tere mimiti wera (Q/t) te mea mōrahi mēnā ko te koki i hangaia e te hihi o te rā me te rārangi poutū ki te mata o te whenua = 0.o (cos 0 = 1). I te nuinga o te wā, ka puta tēnei i te awatea, i te wā e tū poutū ana te rā ki te mata o te whenua. Nō reira, kāore he take e miharo ai mēnā he wera ake te awatea i te ata, i te ahiahi rānei. I te ata me te ahiahi, ko te koki i hangaia he tata ki te 90.o.
Mena he 80 te koki i hangaiao, ko te tere mimiti wera ko:
Ko te tere mimiti wera (Q/t) i te ata me te ahiahi he iti rawa nā te mea e tata ana a cos θ ki te kore. Ko te iti o te cos θ, ko te iti ake o te tere mimiti wera.
I te tōnga o te rā i te pae hauauru, i te aranga ake rānei i te pae rawhiti, ko te koki i hangaia = 90o.
Nā te mea ko te koki i hangaia he 90o, ko te tere mimiti wera ko:
Te tere mimiti wera (Q/t) i te torengitanga o te rā, i te tata rānei te aranga ake = 0.
