Iyini isisindo, kanjani ukubala, futhi ukuthi lihluke kanjani isisindo?

Concept ngawo esiyazi kusukela ebuntwaneni zakuqala, - isisindo. Nokho, ngokuhamba physics ezifundweni zayo kuhilele ubunzima obuthile. Ngakho-ke, kumelwe ichaze ngokucacile lokho isisindo. Kungenziwa kanjani liphinde litholakale kuphi? Futhi kungani akulingani isisindo?

Ukunqunywa mass

umuzwa wemvelo-yesayensi lesi silinganiso ukuthi inquma inani ketshezi eziqukethwe umzimba. Ukuze ukuqokwa ezivamile ukusebenzisa Latin incwadi m. Yokukala ohlelweni standard kilogram. Esikhathini izinkinga zokuphila kwansuku zonke futhi wayevame non-SI: igremu, futhi ithani.

Ngokuhamba isikole kuyoziqeda umbuzo physics: "Yini le isisindo" inikezwa ekutadisheni lo mkhuba inertia. Khona-ke lokhu kubizwa ngokusentshenziswa ekhonweni lomzimba lokukwazi ukuba simelane ushintsho ukuthi lingakanani ijubane lokuya yabo. Ngakho-ke, ebizwa nangokuthi i-mass inertial.

Iyini isisindo?

Okokuqala, ungamandla kuyinto le-vector. Isisindo futhi ubuningi scalar. Isisindo Vector njalo exhunywe ukwesekwa noma ukumiswa futhi siqondiswe luhamba luye ohlangothini olulodwa njengoba amandla adonsela phansi, okusho ukuthi, zibheka phansi.

Ifomula ukubala isisindo kuxhomeke ekutheni lesi ukwesekwa ihamba (ukumiswa). Endabeni lonke uhlelo usebenzisa igama:

P = m * g, lapho F (e imithombo isiNgisi esasikhulunywa incwadi W) - isisindo, g - ukusheshisa gravity. G ngoba izwe kuthathwe lithathwe njengendlela 9.8 m / s ^2.

Kule isisindo ifomula kungenziwa etholakala: m = F / g.

Lapho uya phansi, okungukuthi, e-isisindo isinyathelo, inani layo incipha. Ngakho-ke, ifomula kuba:

P = m (g - a). Lapha, "a" - kuyinto ukusheshisa uhlelo ukunyakaza.

Okusho ukuthi, lapho ukulingana yalezi accelerations ezimbili isimo isisindo kwenzeka lapho isisindo somzimba ilingane no-zero.

Lapho umzimba uqala ukuya phezulu, bese ukhulume isisindo somzimba. Kulesi simo, kukhona isimo sindisa. Ngenxa yokuthi ukwehlisa umzimba kwandisa, futhi ifomula kwakuyoba libukeke kanje:

P = m (g + a).

Njengoba mass ihlobene kwabantu?

elula kakhulu. I kwabantu enkulu yokwaziswa zazo umzimba siqukethe, ukubaluleka ngaphezulu kuyoba isisindo salo. Ngoba kwabantu kuchazwa njengoba isilinganiso amanani amabili. Eyokuqala ivolumu mass - yesibili. Selisho lesi silinganiso ukhethe ngesiGreki incwadi ρ. Yokukala iyona ratio amakhilogremu kumuntu imitha cubic.

Kususelwa bonke ngenhla, ifomula uquqaba kuthatha ifomu elilandelayo:

m = ρ * V, lapho V luchazwa ngegama iledere ivolumu umzimba.

inkinga abathandwayo

Ngemva hlandla umbuzo yini isisindo, usungaqala ukubhekana nezinkinga. Labo ukuthi unokuqukethwe bezijabulisa nentshisekelo kakhudlwana abafundi.

Umsebenti № 1. Izimo: Wini Phu lithole ezimbili ezifanayo ilitha imbiza. Ngo omunye wabo, uju, amafutha kwesinye. Ngazi kanjani lapho uju ngaphandle kokuvula kubo?

Isinqumo. uju ukuminyana obukhulu kunobukaJohane uwoyela. Eyokuqala inenani 1430 kg / m ^3, kanti eyesibili - 920 kg / m ^3. Ngakho-ke, nge esilinganayo izimbiza ukuthi uju kuyoba ezisindayo.

Ukuze impendulo eqonde kakhulu yombuzo yenkinga ubale nenqwaba noju lwezinyosi namafutha ebhodweni. Umthamo aziwayo zabo - 1 ilitha. Kodwa izibalo kunenani e cubic metres. Ngakho-ke, kumelwe siqale afeze lo msebenzi wokuhumusha. Kokunye m ³ iqukethe 1000 amalitha. Ngakho-ke, uma umphumela ukubala liyadingeka ukuthatha ukubaluleka ivolumu elilingana 0,001 ^M3.

Manje ingasetshenziswa isisindo ifomula, lapho inhlanganiso iphindwe ivolumu. Ngemva izibalo ezilula ezifana etholwe amagugu mass: 1.43 kg kanye 0,92 kg noju lwezinyosi namafutha ngokulandelana.

Impendulo: Imbiza uju nzima.

Umsebenzi inombolo 2. Isimo: Clown ucosha isisindo ngaphandle kwezinkinga, ku okulotshiwe, ukuthi isisindo sakhe kuyinto 500 kilograms. Uyini mass langempela le isisindo, uma ilingana yenqwaba 5 amalitha, futhi leso sidakamizwa ngalo senziwa, - i-plug?

Isinqumo. Ethebuleni udinga ukuthola ukubaluleka kukakhokho kwabantu. Kuyinto elilingana 240 kg / m ^3. Manje kudingeka ukuhumusha ukubaluleka ivolumu, uthola 0,005 m ^3.

Ukwazi lezi zimiso akunzima ukusizakala ifomula eyaziwa kakade ukubala nenqwaba isisindo inkohliso. It is etholwe elilingana 1.2 kg. Manje ngiyaqonda ukuthi kungani izinto ezingasile Akunzima.

Impendulo. Ungqimba langempela isisindo 1.2 kg.

Inkinga № 3. Izimo: Genie abahlezi tube, ivolumu zazo alwaziwa. Kodwa inhlanganiso zayo ngalesi sikhathi kwaba 40000 kg / m ^3. Lapho ededelwa ibhodlela, sekuyinto wesiko ukuba kwemigomo nomzimba womuntu: ivolumu 0.08 m ^3, ukuminyana 1000 kg / m ^3. Iyini ivolumu kwesibani?

Isinqumo. Okokuqala okudingeka ukwazi isisindo sayo esimweni esejwayelekile. Kuzoba elilingana 80 kg. Manje singakwazi udlulela ekutholeni okukhiphayo isibani. Sicabanga ukuthi Jean ithatha sonke isikhala ngaphakathi kuye. Khona-ke kufanele ehlukaniswe kwabantu uyaca, ie 80 kuya 40,000 uthole ukubaluleka 0.002 m ^3. Lokho kulingana amalitha amabili.

Impendulo. Umqulu kwesibani ilingana 2 amalitha.

Izinselelo ukubala mass

Kuchubeka ingxoxo mayelana nokuthi iyiphi mass, kufanele kube isinqumo imisebenzi ehlobene nokuphila. izimo ezimbili ziboniswa lapha, okuyinto ekhombisa isicelo yolwazi practice.

Umsebenzi inombolo 4. Isimo: ngamaloli ngozi yenzeke, okwaphumela amafutha hit Gulf ngo-1979. indawo walo kwakunamafasitela ububanzi 640 m kanye ukushuba mayelana 208 cm. Ingabe isisindo lamafutha ezichithekile?

Isinqumo. Amafutha ukuminyana 800 kg / m ^3. Ukuze ukusizakala ifomula ayesevele aziwa, odinga ukukwazi ivolumu izindawo. Kulula ukubala, uma sithatha indawo ye isilinda. Khona-ke ifomula ngoba ivolumu kuyoba:

V = π * r ² * h.

Kulokhu r - iyona engaba futhi h - ukuphakama uMbhalo. Uzothola alinganayo 668,794.88 ^M3. Manje ungakwazi ukubala mass. Kwenzeka kanje: 535034904 kg.

Impendulo: I-oli isisindo cishe 535.036 amathani.

Umsebenti № 5. Izimo: ubude isikhathi eside ngocingo ikhebula kuyinto 15151 km. Iyini isisindo zethusi, okuyinto bangena womshini yayo, uma kwesigaba wire ISIPHAMBANO 7.3 cm ^2?

Isinqumo. inhlanganiso nethusi 8900 kg / m ^3. Lokufuduka kuyinto ngefomula okuyindawo ehlanganisa isisekelo umkhiqizo izinyawo ukuphakama (lapha ubude ikhebula) isilinda. Kodwa okokuqala kudingeka ukuguqula le ndawo e square metres. Lokho uhlukaniswa uba enomborweni enikelweko 10000. Ngemva ukubala kuvela ukuthi umthamo isamba ikhebula cishe elilingana 11000 m ^3.

Manje kudingeka uphindaphinde ukuminyana futhi ivolumu ukuthola, uyini isisindo. Umphumela eziningi 97900000 kg.

Impendulo: isisindo nethusi amathani 97900.

Enye inkinga ehlobene nokubukisa mass

inombolo Lwemisebenzi 6. Isimo: I enkulu ikhandlela isisindo 89867 kg has a ububanzi 2,59 m Yini ukuphakama kwalo.?

Isinqumo. Wax ukuminyana - 700 kg / m ^3. Ukuphakama isidingo ukuthola ifomula yevolumu. Okungukuthi, V lihlukaniswe by umkhiqizo π futhi esigcawini engaba.

Futhi ivolumu ibalwa ngesilinganiso kwabantu. Kuyinto elilingana 128,38 ^M3. Ukuphakama efanayo 24,38 m.

Impendulo: Ukuphakama ikhandlela kuyinto 24,38 m.