Ubuningi kanye nokuntanta ngokulinganayo - izinkinga nezixazululo

Ubuningi kanye nokuntanta ngokulinganayo - izinkinga nezixazululo

1. Ibhulokhi elibekwe eziketshezini ezimbili ezinezinhlobo ezahlukene. Kuketshezi u-A, ingxenye engu-0.6 yento isemanzini. Kuketshezi u-B, ingxenye engu-0.5 yento isemanzini. Thola isilinganiso sobuningi boketshezi u-A kuya kuketshezi u-B.

Kwaziwa:

Ubuningi bebhulokhi = x

Ingxenye yento eseketshezini A = 0.6

Ubuningi boketshezi A = y

Ingxenye yento eketshezi B = 0.5

Ubuningi boketshezi B = z

Okufunwayo: Isilinganiso sobuningi boketshezi u-A noketshezi u-B (y:z)

Isixazululo:

Faka u-x esilinganisweni sesi-2 no-x esilinganisweni esingu-1:

2. Into ebekwe ku-P ewuketshezi, ingxenye engu-0.5 yento isuke iwuketshezi. Uma into ibekwe ku-Q ewuketshezi, into isuke iwuketshezi, njengoba kuboniswe esithombeni esingezansi. Iyini isilinganiso sobuningi be-P ewuketshezi ku-Q ewuketshezi?

Kwaziwa:

Ubuningi bento = x

Ingxenye yento ewuketshezi P = 1/2 = 0.5

Ubuningi boketshezi P = y

Ingxenye yento ewuketshezi Q = 1

Ubuningi boketshezi Q = z

Okufunwayo: Isilinganiso sobuningi be-P ewuketshezi ku-Q ewuketshezi (y: z)

Isixazululo:

Faka u-x esilinganisweni sesi-2 no-x esilinganisweni esingu-1:

3. Izinkuni ezintanta emafutheni (ubuningi bamafutha bungu-800 kg/m3 ⁾ . Izingxenye ezingu-4/5 zezinkuni zikuwoyela . Kuyini ubuningi bokhuni?

Kwaziwa:

Ubuningi bamafutha (ρ) = 800 kg/m ^-3

Ingxenye yokhuni emafutheni = 4/5

Okufunwayo: Ubuningi bokhuni

Isixazululo:

Ubuningi bokhuni bungu-640 kg/ ^m3.

4. Isisindo sebhulokhi singama-N angu-50. Emanzini, isisindo sebhulokhi singama-N angu-30. Uma ubuningi bamanzi bungu-10 ³ kg/m ^-3 buyini ubuningi bebhulokhi.

Kwaziwa:

Isisindo sebhulokhi emoyeni (w) = 50 N

Isisindo sebhulokhi emanzini (w _amanzi ) = 30 N

Ubuningi bamanzi (ρ _amanzi ) = 10 ³ kg/m ³ = 1000 kg/m ³

Ukusheshisa ngenxa yamandla adonsela phansi (g) = 10 m/s ²

Isisindo sebhulokhi (m) = w/g = 50/10 = 5 kg

Okufunwayo: Ubuningi bamabhulokhi ( _amabhulokhi e-ρ )

Isixazululo:

Amandla amakhulu:

F _A = ​​​​w – w _amanzi = 50 – 30 = 20 N

Umthamo webhulokhi emanzini:

F _A = ​​​​ρ g V

20 = (1000)(10) V

20 = (10,000) V

V = 20/10,000

V = 0.002 m ³

Ubuningi bebhulokhi:

ρ = m/V = 5 / 0.002 = 2500 kg/m ³

5. Ibhloko lokhuni elicwiliswe emanzini. 25% wezingxenye zalo zingaphezu kwamanzi kanti 75% zisemanzini. Ubuningi bamanzi buyi- 1 g/cm3 ^kanti ukusheshisa ngenxa yamandla adonsela phansi kuyi- 10 m/s2 ^. Thola ubuningi bamabhlogo.

A. 0.025 kg/ ^m3

B. 0.075 g/ ^cm3

C. 0.250 kg/ ^m3

D. 0.750 g/ ^cm3

Kwaziwa:

Ingxenye yamabhulokhi angaphezu kwamanzi = 25% = 25/100 = 0.25

Ingxenye yebhulokhi emanzini = 75% = 75/100 = 0.75

Ubuningi bamanzi (ρ _amanzi ) = 1 g/cm3 ⁼ 1000 kg/ ^m3

Ukusheshisa ngenxa yamandla adonsela phansi = 10 m/s ²

Okufunwayo: Ubuningi bamabhulokhi ( _amabhulokhi e-ρ )

Isixazululo:

Umthamo wamabhulokhi emanzini = isilinganiso sobuningi bamabhulokhi nobuningi bamanzi

Impendulo efanele ngu-D.

1. Kuyini ubuningi, futhi kuchazwa kanjani ngokwezibalo?
   • Impendulo: Ubuningi buyindlela yokulinganisa ukuthi buningi kangakanani ubunzima obuqukethwe kuvolumu ethile. Ngokwezibalo, kuchazwa ngokuthi ubuningi =ubukhulu/umthamo​.
2. Ubuningi bento bunquma kanjani ukuthi izontanta noma izocwila oketshezini?
   • Impendulo: Uma ubukhulu bento bungaphansi kobukhulu boketshezi olubekwe kulo, into izontanta. Ngokuphambene nalokho, uma ubukhulu bento bukhulu kunobukhulu boketshezi, izocwila.
3. Iyini isimiso esingemuva kokuntanta noma ukucwila kwento oketshezini?
   • Impendulo: Isimiso yi-Archimedes' Principle, ethi umzimba ucwiliswa olwazini loketshezi lwamandla aphezulu akhuphukayo alingana nesisindo soketshezi olususwayo.
4. Uma i-ice cube intanta emanzini kanti ingxenye yayo ingaphezu kwamanzi, lokhu kubonisani ngobuningi beqhwa namanzi?
   • Impendulo: Lokhu kubonisa ukuthi ubukhulu beqhwa bungaphansi kobukhulu bamanzi. Yingakho i-ice cube intanta, futhi ingxenye yayo kuphela ehlala ingaphansi kwamanzi ukuze isuse inani lamanzi elilingana nesisindo se-ice cube.
5. Kungani imikhumbi yensimbi esindayo intanta emanzini kuyilapho isipikili esincane sensimbi singase sicwile?
   • Impendulo: Ubuningi bomkhumbi wensimbi, okuhlanganisa nezingxenye zawo eziyizimbobo ezigcwele umoya, bungaphansi kobuningi bamanzi. Ngokuphambene nalokho, ubukhulu besipikili sensimbi eqinile bukhulu kunobuningi bamanzi, okubangela ukuba ucwile.
6. Umqondo wokuthi “ukuntanta okungathathi hlangothi” uhluke kanjani ekuntanteni noma ekucwileni?
   • Impendulo: Ukuntanta okungathathi hlangothi kwenzeka lapho isisindo sento silinganiswa kahle ngamandla okuntanta, okubangela ukuba into ihlale ilenga ngaphakathi koketshezi ngaphandle kokukhuphuka noma ukucwila.
7. Kungani ibhaluni le-helium lintanta emoyeni?
   • Impendulo: Ubuningi be-helium buncane kakhulu kunobuningi bomoya. Ngenxa yalokho, isisindo sebhaluni le-helium (kufaka phakathi izinto zebhaluni kanye ne-helium engaphakathi) sincane kunesisindo somoya eliwususayo, okwenza untante.
8. Kwenzekani ngobuningi bento uma icindezelwa ibe yivolumu encane kuyilapho isisindo sayo sihlala singaguquguquki?
   • Impendulo: Ubuningi buzokhula njengoba ubuningi buchazwa njengobuningi obuhlukaniswe ngevolumu. Uma ivolumu yehla futhi ubunzima buhlala bunjalo, isilinganiso (ubuningi) sizokhula.
9. Usawoti uthinta kanjani ubuningi bamanzi?
   • Impendulo: Ukwandisa usawoti wamanzi (okungukuthi, ukwengeza usawoti owengeziwe) kuzokwandisa ubuningi bawo. Yingakho izinto zivame ukuntanta kalula emanzini anosawoti (njengoLwandle Olufile) uma kuqhathaniswa namanzi ahlanzekile.
10. Uma into intanta ngokulingana oketshezini, amandla athambile kanye namandla adonsela phansi entweni aqhathaniswa kanjani?

• Impendulo: Uma into intanta ngokulingana, amandla okuphapha (amandla aphezulu ngenxa yoketshezi) ayalingana ngobukhulu futhi aphambene nohlangothi lwamandla adonsela phansi (isisindo) asebenza entweni.