Ukwanda kokushisa - izinkinga nezixazululo

Ukwanda kokushisa - izinkinga nezixazululo

Ukwandiswa kwendawo

1. Ishidi lensimbi ku-20 ^o C linosayizi njengoba kuboniswe esithombeni esingezansi. Uma i-coefficient yokwanda okuqondile kwensimbi ingu-10 ^{-5 o} C ^-1 , pho luyini ushintsho endaweni ku-60 ^o C.

Kwaziwa:

Ubude bensimbi = 40 cm

Ububanzi bensimbi = 20 cm

Isiqalo sendawo yensimbi (Ao ₎ = (40)(20) = 800 cm ²

I-coefficient yokwanda okuqondile (α) = 10 ^{-5 o} C ^-1

I-coefficient yokwandiswa kwendawo (β) = 2 x i-coefficient yokwandiswa okuqondile (2α) = 2 x 10 ^{-5 o} C ^-1

Ushintsho lokushisa (ΔT) = 60 ^o C – 20 ^o C = 40 ^o C

Okufunwayo: Ushintsho endaweni yensimbi ku-60 ^o C

Isixazululo:

Isibalo sokwandiswa kwendawo:

ΔA = β A _o ΔT

ΔA = ukwanda kwendawo yensimbi, β = I-coefficient yokwandiswa kwendawo, A _o = indawo yokuqala, ΔT = ushintsho lokushisa = izinga lokushisa lokugcina - izinga lokushisa lokuqala

Ukwanda kwendawo yensimbi:

ΔA = β A _o ΔT

ΔA = (2 x 10 ^-5 )(800)(40) = 0.64 cm

2. Ipuleti lensimbi ku-20 ^o C liboniswe esithombeni esingezansi. Uma izinga lokushisa likhuphukela ku-100 ^o C futhi i-coefficient yokwanda kwensimbi okuqondile ingu-1.1 x 10 ^{-7 o} C ^-1 , khona-ke iyiphi indawo yokugcina yepuleti.

Kwaziwa:

Ubude bepuleti = 2 m

Ububanzi bepuleti = 2 m

Indawo yokuqala yensimbi (Ao ₎ = (2)(2) = 4 ^m2

I-coefficient yokwanda okuqondile kwensimbi (α) = 1.1 x 10 ^{-7 o} C ^-1

I-coefficient yokwandiswa kwendawo yensimbi (β) = 2 x i-coefficient yokwandiswa okuqondile kwensimbi (2α) = 2.2 x 10 ^{-7 o} C ^-1

Ushintsho lokushisa (ΔT) = 100 ^o C – 20 ^o C = 80 ^o C

Okufunwayo : Indawo yensimbi ku-100 ^o C

Isixazululo:

Ukwanda kobude:

ΔA = β A _o ΔT

ΔA = (2.2 x 10 ^-7 )(4)(80) = 704 x 10 ^-7 = 0,0000704 m ²

Indawo yensimbi:

Indawo yensimbi = indawo yokuqala + ukwanda kwendawo

Indawo yensimbi = 4 m ² + 0.0000704 m ²

Indawo yensimbi = 4.0000704 ^m2

3. Ipuleti lethusi elinesilinganiso sokunwebeka okuqondile α = 18.10 ^{-6 o} C ^-1 ku-0 ^o C linosayizi njengoba kuboniswe esithombeni esingezansi. Uma ipuleti lishiswa ku-80 ^o C, pho kuyini ukwanda kwendawo yepuleti.

Kwaziwa:

Ubude bethusi = 40 cm = 0.4 amamitha

Ububanzi bethusi = 20 cm = 0.2 amamitha

Indawo yokuqala yethusi (Ao ₎ = (0.4)(0.2) = 0.08 ^m2

I-coefficient yokwandiswa okuqondile kwethusi (α) = 18 x 10 ^{-6 o} C ^-1

I-coefficient yokwandiswa kwendawo yethusi (β) = 2 x I-coefficient yokwandiswa okuqondile (2α) = 36 x 10 ^{-6 o} C ^-1

Ushintsho lokushisa (ΔT) = 80 ^o C – 0 ^o C = 80 ^o C

Okufunwayo: Ukwanda kwendawo yethusi ku-80 ^o C

Isixazululo:

Ukwanda kwendawo yethusi:

ΔA = β A _o ΔT

ΔA = (36 x 10 ^-6 )(0.08)(80) = 230.4 x 10 ^-6 = 2.304 x 10 ^-4 m ²

Ukunwetshwa kwevolumu

4. Isitsha sengilazi esinomthamo wamalitha ama-4 agcwele amanzi, bese sishiswa kuze kube yilapho izinga lokushisa likhuphuka libe ngu-20 ^o C. Amanye amanzi achitheka. I-coefficient yokwanda okuqondile kwengilazi = 9 x 10 ^{-6 o} C ^-1 ; i-coefficient yokwanda kwevolumu yamanzi = 2.1 x 10 ^{-4 o} C ^-1 . Nquma ivolumu yamanzi achithekayo.

Kwaziwa:

Umthamo wokuqala wegesi namanzi (Vo₂o₂ ₎ = amalitha ama-4

Ukwanda kwezinga lokushisa kwengilazi namanzi (ΔT) = 20 ^o C

I-coefficient yokwandiswa okuqondile kwengilazi (α) = 9 x 10 ^{-6 o} C ^-1

I-coefficient yokwandisa ivolumu yengilazi (γ) = 3α = 3 (9 x 10 ^{-6 o} C ^-1 ) = 27 x 10 ^{-6 o} C ^-1

I-coefficient yokwandisa ivolumu yamanzi (γ) = 2.1 x 10 ^{-4 o} C ^-1

Kufunwa: Umthamo wamanzi achithekile

Isixazululo:

Isibalo sokwandiswa kwevolumu:

V = Vo _o + γ Vo _o ΔT

V – Vo _o = γ Vo _o ΔT

ΔV = γ Vo _o ΔT

V = ivolumu yokugcina , Vo _o = ivolumu yokuqala , ΔV = ushintsho kuvolumu , γ = i-coefficient yokwandiswa kwevolumu , ΔT = ushintsho kumazinga okushisa.

Ushintsho kuvolumu yesitsha sengilazi:

ΔV = γ Vo _o ΔT = (27 x 10 ^-6 )(4)(20) = 2160 x 10 ^-6 = 2.160 x 10 ^-3 = 0.002160 amalitha

Ushintsho kumthamo wamanzi:

ΔV = γ Vo _o ΔT = (2.1 x 10 ^-4 )(4)(20) = 168 x 10 ^-4 = 0.0168 amalitha

Ushintsho kumthamo wamanzi lukhulu kunesitsha sengilazi, ngakho-ke amanye amanzi ayachitheka.

Umthamo wamanzi achithekile:

Amalitha angu-0.0168 – amalitha angu-0.002160 = amalitha angu-0.01464 = amalitha angu-0.015

5. Isitsha sensimbi (isilinganiso sokwanda okuqondile = 10 ^{-5 o} C ^-1 ) esinevolumu yamalitha ayi-6 agcwele i-acetone (isilinganiso sokwanda kwevolumu = 1.5 x 10 ^{-3 o} C ^-1 ). Uma isitsha kanye ne-acetone kushiswa kusuka ku-0 ^o C kuya ku-40 ^o C, lingakanani ivolumu ye-acetone echithekile?

Kwaziwa:

Umthamo wokuqala wesitsha kanye ne-acetone (Vo₂o₂ ₎ = amalitha ayi-6

Ushintsho lokushisa kwesitsha kanye ne-acetone (ΔT) = 40 ^o C

I-coefficient yokwandiswa okuqondile kwensimbi (α) = 10 ^{-5 o} C ^-1

I-coefficient yokwandisa ivolumu yensimbi (γ) = 3α = 3 (10 ^{-5 o} C ^-1 ) = 3 x 10 ^{-5 o} C ^-1

I-coefficient yokwandisa ivolumu ye-acetone (γ) = 1.5 x 10 ^{-3 o} C ^-1

Okufunwayo: Umthamo we-acetone echithekile

Isixazululo:

Isibalo sokwandiswa kwevolumu:

ΔV = γ Vo _o ΔT

ΔV = ushintsho kuvolumu , γ = i-coefficient yokwandiswa kwevolumu , Vo ₌ ivolumu yokuqala , ΔT = ushintsho kumazinga okushisa.

Ushintsho kuvolumu yesitsha sensimbi:

ΔV = γ Vo _o ΔT = (3 x 10 ^-5 )(6)(40) = 720 x 10 ^-5 = 0.00720 amalitha

Ushintsho lwevolumu ye-acetone egazini:

ΔV = γ Vo _o ΔT = (1.5 x 10 ^-3 )(6)(40) = 360 x 10 ^-3 = 0.360 amalitha

Ushintsho kuvolumu ye- acetone lukhulu kunesitsha sensimbi , ngakho-ke amanye amaphilisi e-acetone.

Umthamo we-acetone ochithekile:

Amalitha angu-0.360 – amalitha angu-0.00720 = amalitha angu-0.3528 = amalitha angu-0.35

1. Kuyini ukwanda kokushisa?
   • Impendulo: Ukwanda kokushisa kubhekisela ekuthambekeleni kwezinto ukushintsha ivolumu yazo ngenxa yokushintsha kwezinga lokushisa.
2. Ukwanda kokushisa kuthinta kanjani ubuningi bento ethile?
   • Impendulo: Njengoba into ikhula ngokushisa, umthamo wayo uyanda, okuholela ekunciphiseni ubuningi bayo, uma kuthiwa isisindo sayo sihlala singaguquguquki.
3. Kungani kukhona izikhala phakathi kwezingxenye zamabhuloho nemizila yesitimela?
   • Impendulo: Lezi zikhala, ezivame ukubizwa ngokuthi ama-expansion joints, zenzelwe ukwamukela ukwanda nokufinyela kwezinto ngenxa yokushintsha kwezinga lokushisa, ukuvimbela ukuguquka noma umonakalo ongaba khona.
4. Uyini umehluko phakathi kokwandiswa okuqondile, okunevolumu, kanye nendawo?
   • Impendulo: Ukwandiswa okuqondile kubhekisela ekushintsheni kobukhulu obubodwa (njengobude benduku); ukwandiswa kwendawo kubhekisela ekushintsheni kobukhulu obubili (njengobuso beshidi); kanti ukwandiswa kwevolumu kuhlobene noshintsho kuzo zonke izilinganiso ezintathu (njengomthamo woketshezi).
5. I-coefficient yokwanda okuqondile inqunywa kanjani?
   • Impendulo: Kuchazwa njengoshintsho oluyingxenye ngobude ngedigri ushintsho lokushisa ngokucindezela okungaguquki. Kwinto ethile, ushintsho lobude (∆L) olubangelwa ushintsho lokushisa (∆T) lunikezwa yi ∆L=αL₀​∆T, lapho L₀​ ubude bokuqala kanye $\alpha$ yi-coefficient yokwanda okuqondile.
6. Kungani imichilo ye-bimetallic igoba lapho ifudunyezwa noma ipholisiwe?
   • Impendulo: I-bimetallic strip yakhiwa izinsimbi ezimbili ezahlukene ezihlanganiswe ndawonye. Njengoba insimbi ngayinye ine-coefficient yayo yokwanda kokushisa, iyakhula noma inciphe ngamazinga ahlukene lapho izinga lokushisa lishintsha. Lokhu kukhula okuhlukile kubangela ukuthi i-strip igobe.
7. Isenzakalo sokwanda kokushisa sihlobene kanjani nokwenyuka kwamazinga olwandle?
   • Impendulo: Ingxenye yokwenyuka kwamazinga olwandle ingabangelwa ukwanda kwamanzi olwandle okushisa. Njengoba izinga lokushisa loMhlaba likhuphuka, izilwandle ziyafudumala, okuholela ekwandeni kwamanzi kanye nokwenyuka kwamazinga olwandle okulandelayo.
8. Kwenzekani “ekwandeni kwamanzi okungajwayelekile”?
   • Impendulo: Ngokungafani nezinto eziningi, amanzi ayakhula njengoba ephola kusuka ku-4°C kuya ku-0°C, bese encipha uma eqandisa. Lokhu okungajwayelekile kusho ukuthi amanzi anobukhulu bawo obukhulu ku-4°C. Yingakho iqhwa (elingaxinene kakhulu kunamanzi acwebezelayo) lintanta emanzini.
9. Kungani ukwanda kokushisa kubalulekile kwezobunjiniyela nakwezokwakha?
   • Impendulo: Izinto zokwakha ziyanda noma zinciphe njengoba amazinga okushisa eshintsha. Ngaphandle kokubala ukwanda kokushisa, izakhiwo zingase zibhekane nokucindezeleka okungadingekile, ukuguquka, noma ukwehluleka. Onjiniyela nabakhi bezakhiwo bafaka izici zokuklama ukuze baphathe lezi zinguquko ngokuphephile.
10. Ingabe ukunwetshwa kokushisa kungabuyiselwa emuva?

• Impendulo: Yebo, ngokuvamile uma into ipholile, izoncipha ngokushisa, okuphambene nokukhula ngokushisa. Izinga kanye nohlobo lwalokhu kuncipha kuzoncika ezintweni kanye nezimo.