Poʻomanaʻo: Nā nīnau hoʻohālike no nā ʻano nalu
He manaʻo koʻikoʻi nā nalu i ka physics, me nā hoʻohana he nui i ke ola o kēlā me kēia lā, mai ke kamaʻilio ʻana a me ka hoʻokele ʻana a hiki i nā ʻenehana lapaʻau. Ma kēia ʻatikala, e kūkākūkā mākou i nā ʻano nalu like ʻole, me nā laʻana e kōkua i ka hoʻoikaika ʻana i ko mākou ʻike i kēia kumuhana.
Hoʻolauna i ka Manaʻo o nā Nalu
ʻO nā nalu he mau haʻalulu e holo ana ma waena o kahi waena a i ʻole kahi ākea. Hiki ke hoʻokaʻawale ʻia nā nalu i ʻelua mau ʻāpana nui: nā nalu mechanical a me nā nalu electromagnetic. Pono nā nalu mechanical i kahi waena e hoʻolaha ai, e like me nā nalu kani e holo ana ma ka lewa, ka wai, a i ʻole nā mea paʻa. ʻAʻole pono nā nalu electromagnetic, e like me ke kukui, nā nalu lekiō, a me nā kukuna X, i kahi waena a hiki ke hoʻolaha i loko o kahi hakahaka.
Nā ʻAno o nā Nalu
1. Nā Nalu Mekanika
– Nā Nalu Longitudinal: Ma kēia mau nalu, ua like nā haʻalulu o ka waena me ke kuhikuhi o ka laha ʻana o ka nalu. ʻO kahi laʻana maʻamau o kahi nalu longitudinal he nalu kani. Ma nā nalu longitudinal, haʻalulu nā ʻāpana o ka waena i mua a i mua e like me ke kahe o ka ikehu.
– Nā Nalu Transverse: Ma kēia mau nalu, kū pololei nā haʻalulu o ka waena i ke kuhikuhi o ka laha ʻana o ka nalu. ʻO nā hiʻohiʻona o nā nalu transverse he mau nalu ma ke kaula a i ʻole nā nalu māmā.
2. Nā Nalu Uila
ʻO nā nalu electromagnetic e komo pū ana me nā nalu lekiō, nā microwaves, infrared, ka mālamalama ʻike ʻia, ultraviolet, nā kukuna X, a me nā kukuna gamma. Loaʻa i kēia mau nalu a pau ka wikiwiki like i loko o kahi hakahaka, ʻo ia ka wikiwiki o ka mālamalama, ma kahi o \(3 \times 10^8\) m/s.
3. Nā Nalu ʻIli
ʻO nā nalu ʻilikai nā nalu e pālahalaha ana ma ka ʻili o kahi mea waena, e like me nā nalu wai ma luna o ka ʻili o ke kai.
Nā Nīnau Laʻana a me ke Kūkākūkā
No ka hoʻomaopopo maikaʻi ʻana i kēia manaʻo, e nānā kākou i kekahi mau pilikia hoʻohālike:
Laʻana Nīnau 1: Nā Nalu Longitudinal
Nīnau: He 500 Hz ka alapine (frequency) o kahi nalu kani a hele i ka lewa me ka wikiwiki o 340 m/s. He aha kona nalu?
Kūkākūkā: Hiki iā kākou ke hoʻohana i ke kaulike kumu o nā nalu:
\[
v = f manawa \lambda
\]
kahi ʻo \(v\) ka wikiwiki (340 m/s), ʻo \(f\) ke alapine (500 Hz), a ʻo \(\lambda\) ka nalu a mākou e makemake ai e ʻimi. Ma ka hoʻonohonoho hou ʻana i ka hoohalike, hiki iā mākou ke loaʻa ka nalu:
\[
\lambda = \frac{v}{f} = \frac{340}{500} = 0,68 \text{ m}
\]
No laila, ʻo ka nalu o ke kani he 0,68 mika.
Laʻana Nīnau 2: Nā Nalu Transverse
Nīnau: He 2 mika ka lōʻihi o ka nalu o kahi nalu transverse ma ke kaula. Inā he 2 Hz kona alapine (frequency), e hoʻoholo i ka wikiwiki o ka nalu.
Kūkākūkā: Hoʻi mākou i ka hoʻohana ʻana i ka hoʻohālikelike kumu like:
\[
v = f manawa \lambda
\]
Hāʻawi ʻia ʻo \(f = 2\) Hz a me \(\lambda = 2\) m, a laila:
\[
v = 2 \times 2 = 4 \text{ m/s}
\]
ʻO 4 m/s ka wikiwiki o ka nalu.
Laʻana Nīnau 3: Nā Nalu Uila
Nīnau: He 600 nm ka lōʻihi o ka nalu o kahi nalu māmā. He aha ke alapine (frequency) o ka nalu? (E hoʻohana i ka wikiwiki o ka mālamalama \(c = 3 \times 10^8\) m/s)
Kūkākūkā: ʻO ka mea mua, e hoʻololi i ka nalu mai nā nanometer i nā mika: 600 nm = \(600 \times 10^{-9}\) m. A laila e hoʻohana i ka hoohalike:
\[
c = f manawa \lambda
\]
\[
f = \frac{c}{\lambda} = \frac{3 \times 10^8}{600 \times 10^{-9}}
\]
\[
f = \frac{3 \times 10^8}{6 \times 10^{-7}} = 5 \times 10^{14} \text{ Hz}
\]
ʻO ke alapine (frequency) o ka nalu māmā he \(5 \times 10^{14}\) Hz.
Keʻena Hoʻokolohua Nalu a me nā Hoʻohana i ke Ola o kēlā me kēia lā
He mea nui ka hoʻomaopopo ʻana i nā nalu ʻaʻole wale ma ke kumumanaʻo akā i nā noi honua maoli. ʻO kekahi mau noi koʻikoʻi o nā nalu:
1. Kelekamaʻilio: Hoʻohana ʻia nā nalu lekiō a me nā microwave i nā kelepona paʻalima, Wi-Fi, a me nā hoʻolaha kīwī.
2. Lapaʻau: Hoʻohana ʻia nā nalu ultrasonic i ka ultrasound, ʻoiai hoʻohana ʻia nā kukuna X i ke kiʻi lapaʻau.
3. ʻOihana a me ka Hoʻokele: Hoʻohana ʻia ka radiation infrared i nā mea ana wela, a hoʻohana ka ʻenehana radar i nā microwaves.
4. Ikehu Hou: Hoʻohana ka ʻenehana mana o ka lā i nā nalu māmā, ʻoiai hiki i ka ʻenehana turbine makani ke hoʻohana pono i nā ʻano nalu makani.
Ka hopena
He ʻāpana koʻikoʻi nā nalu o ka physics, e hoʻopilikia ana i nā ʻano like ʻole o ko kākou ola. ʻO ka hoʻomaopopo ʻana i nā ʻano nalu a me ko lākou mau ʻano e kōkua iā mākou e hoʻopili i ka ʻenehana o kēlā me kēia lā a hoʻomaikaʻi i ko mākou ʻano ola. Ma ke aʻo ʻana a me ka hoʻomaopopo ʻana i nā manaʻo kumu a me ka hoʻoponopono ʻana iā lākou ma o nā pilikia hoʻohālike, hiki iā mākou ke kū maʻalahi i nā pilikia i ka ʻepekema a me ka ʻenekinia e hoʻohana ana i nā kumumanaʻo nalu.
