Ihe atụ nke Ajụjụ Ngwa Sound Wave
Ebili ụda bụ ihe a na-ahụkarị ná ndụ kwa ụbọchị. Site na ụda mkpu ụtụtụ gị ruo n'okwu ọnụ, ụda na-arụ ọrụ dị mkpa na ndụ mmadụ. Na fiziki, a na-amụ ebili ụda nke ọma iji ghọta njirimara ha, omume ha, na ojiji ha n'ọtụtụ ngalaba. Isiokwu a ga-atụle ọtụtụ ihe atụ nke ngwa ebili ụda iji nye nghọta ka mma nke isiokwu a.
Ịghọta ebili mmiri ụda
Tupu anyị abanye n'ajụjụ ndị a, ka anyị leba anya n'ihe ebili mmiri ụda bụ. Ebili mmiri ụda bụ ebili mmiri igwe nke na-agafe site na mgbasa ozi na-agbanwe agbanwe dịka ikuku, mmiri, ma ọ bụ ihe siri ike. Ụda na-esi na mkpọtụ nke ihe na-akpata mgbanwe na nrụgide na mgbasa ozi gbara ya gburugburu pụta, mgbanwe a na-agbasakwa dị ka ebili mmiri.
Ebili ụda nwere ihe ndị dị ka ugboro, ogologo ebili, ọsọ, na oke. Ugboro ebili ụda na-ekpebi otú ụda ahụ dị elu ma ọ bụ dị ala, a na-atụ ya na hertz (Hz), ebe oke ebili ahụ na-ekpebi otú ụda ahụ si dị elu.
Ihe atụ nke Ajụjụ Ngwa Sound Wave
A na-eme ajụjụ ndị a iji nwalee nghọta nke otu ụkpụrụ nke ebili mmiri ụda si arụ ọrụ n'ọtụtụ ọnọdụ dị adị n'ụwa.
Ajụjụ nke 1: Mmetụta Doppler na Sirens Ambulance
Ajụjụ: Onye na-ekiri ihe na-eguzo n'akụkụ okporo ụzọ ka ụgbọ ihe mberede na-aga na m30/s. Ọ bụrụ na ọsọ ụda dị n'ikuku bụ m340/s, na ugboro ole siren ahụ bụ 1000 Hz, kedu ugboro ole siren ahụ nụrụ ka ụgbọ ihe mberede ahụ na-abịaru nso ma na-apụ n'ebe ọ nọ?
Nkọwa: Ajụjụ a na-eji echiche nke mmetụta Doppler, nke bụ mgbanwe na ugboro ole ebili mmiri ụda nke onye na-ekiri natara n'ihi mmegharị nke isi iyi ụda ahụ nye onye na-ekiri ya.
Azịza:
1. Mgbe ụgbọ ihe mberede bịakwutere onye na-ekiri ihe nkiri ahụ:
\[
f' = f \left(\frac{v + v_0}{v – v_s}\right)
\]
ebe \(f'\) bụ ugboro ole a nụrụ, \(f\) bụ ugboro ole isi mmalite, \(v\) bụ ọsọ ụda, \(v_0\) bụ ọsọ onye na-ekiri ihe (n'okwu a 0 n'ihi na onye na-ekiri ihe na-anaghị eguzo), na \(v_s\) bụ ọsọ nke isi mmalite (ụgbọala mberede).
\[
f' = 1000 \aka ekpe(\frac{340}{340 – 30}\aka nri) \ihe dịka 1093 Hz
\]
2. Mgbe ụgbọ ihe mberede na-anya ụgbọala:
\[
f' = f \left(\frac{v – v_0}{v + v_s}\right)
\]
\[
f' = 1000 \aka ekpe(\frac{340}{340 + 30}\aka nri) \ihe dịka 915 Hz
\]
Ajụjụ nke Abụọ: Mmetụta dị n'ime Paịpụ mepere emepe
Ajụjụ: Paịpụ akụkụ ahụ mepere emepe n'akụkụ abụọ ya nwere ogologo nke 85 cm. Kedu ugboro ole paịpụ a na-eme ma ọ bụrụ na ọsọ ụda n'ikuku bụ 340 m/s?
Nkọwa: N'ime paịpụ mepere emepe, resonance na-eme mgbe ogologo paịpụ ahụ bụ ọtụtụ nke ọkara wavelength. Maka ụda isi, ogologo paịpụ ahụ hà nhata ọkara wavelength (\(\lambda/2\)).
Azịza:
1. Ogologo \(\lambda\) maka ụda isi (ugboro isi) bụ:
\[
\lambda = 2L = ugboro abụọ 0.85 \ederede{ m} = 1.7 \ederede{ m}
\]
2. A na-agbakọ ugboro ole (\(f\)) site na iji usoro a:
\[
f = \frac{v}{\lambda} = \frac{340}{1.7} \ihe dị ka 200 \ederede{ Hz}
\]
Ajụjụ nke Atọ: Ọkwa Ike na Ọkwa Ike nke Ụda
Ajụjụ: Igwe na-emepụta ụda nwere ike nke 0.5 W. Ọ bụrụ na etinyere igwe ahụ n'ime ụlọ mechiri emechi nke nwere akụkụ nke mita 10, kedu ka ọkwa ụda dị n'etiti ụlọ ahụ si dị? Were ya na ike ụda niile na-apụta n'otu ebe n'akụkụ niile.
Nkọwa: Ike ụda (\(I\)) bụ ike mpaghara otu nkeji. A na-atụ ọkwa ike ụda (\(L\)) na decibels (dB).
Azịza:
1. Gbakọọ ike ụda:
\[
I = \frac{P}{A} = \frac{0.5}{4\pi r^2}
\]
N'etiti ụlọ ahụ, ọkara akụkụ nke kube ahụ (mita 5) dị:
\[
I = \frac{0.5}{4\pi (5)^2} = \frac{0.5}{314} \ihe dị ka 0.00159 \text{ W/m}^2
\]
2. Gbakọọ ọkwa ike ụda (\(L\)) na dB:
\[
L = 10 \log_{10} \left(\frac{I}{I_0}\right)
\]
Ebe \(I_0 = 1 \ugboro 10^{-12} \text{ W/m}^2\) bụ ike ntụaka:
\[
L = 10 \log_{10} \left(\frac{0.00159}{1 \times 10^{-12}}\right) \ihe dịka 92.02 \text{ dB}
\]
Mmechi
Ebili ụda na-arụ ọrụ dị oke mkpa n'ọtụtụ ngalaba, nghọta nke ojiji ha dịkwa oke mkpa na sayensị na teknụzụ. Site n'ịmụ ihe atụ dịka nke dị n'elu, anyị nwere ike ịghọta nke ọma otu ozizi ebili ụda si emetụta ọnọdụ ụwa n'ezie, dịka mmetụta Doppler, resonance na ngwa egwu, na ịtụ ike ụda.
Dịka nwa akwụkwọ ma ọ bụ onye na-eme ihe n'ọrụ a, nghọta dị mma nke echiche ndị bụ isi na ojiji ha ga-eme ka idozi nsogbu na imepụta ihe ọhụrụ na teknụzụ metụtara ụda na ụda olu dị mfe.
