Kuhle ukuthi ihlukaniseke ngo-2
Ngezikhathi ezithile ngihlanganisa izazi zefiziksi engikanye nazo ngokuthi i-physics ngokwayo inzima kakhulu kubo. I-physics yesimanje isiphenduke izibalo eziningi ngo-90%, uma kungenjalo i-100%. Kujwayelekile ukuthi othisha be-physics bakhale ngokuthi abakwazi ukufundisa kahle ngenxa yokuthi abanazo izinsiza zezibalo ezifanele esikoleni. Kodwa ngicabanga ukuthi ezikhathini eziningi ... abakwazi ukufundisa, ngakho-ke bathi kufanele babe nemiqondo efanelekile kanye namasu ezibalo, ikakhulukazi izibalo ezihlukanisayo. Kuyiqiniso ukuthi ngemva kokubala umbuzo kuphela lapho singawuqonda ngokugcwele. Igama elithi "compute" linendikimba evamile negama elithi "face". Bonisa ubuso bakho = kubalwa.
Sasihlezi nozakwethu, isazi sefilosofi sasePoland nesazi sezokuhlalisana kwabantu u-Andrzej, ngasechibini elihle i-Maida, iSuwałki. UJulayi ubebanda kulo nyaka. Angikhumbuli ukuthi kungani ngakhuluma ihlaya elaziwayo ngomshayeli wesithuthuthu owahluleka ukuzibamba, washayisa isihlahla, kodwa wasinda. Ku-ambulensi, wamemeza, "kuhle ukuthi wabelane okungenani ezimbili." Udokotela wamvusa wabuza ukuthi kwenzakalani, ahlukaniseni noma angahlukaniswa kabili. Impendulo yayiwukuthi: mv2.
U-Andrzej wahleka isikhathi eside, kodwa wabuza ngamahlonyana ukuthi i-mv2 imayelana nani. ngikuchazile E = mv2/2 lena ifomula ye amandla we-kinetickusobala uma wazi i- integral calculus kodwa ungayiqondi. Ezinsukwini ezimbalwa kamuva wacela incazelo encwadini ukuze ifinyelele kuye, uthisha wasePoland. Uma kwenzeka, ngithe ayikho imigwaqo yasebukhosini eRussia (njengoba u-Aristotle asho kumfundi wakhe wasebukhosini u-Alexander Omkhulu). Bonke kufanele bahlupheke ngendlela efanayo. O, kuyiqiniso? Phela, umhlahlandlela wezintaba onolwazi uzoqondisa iklayenti endleleni elula kakhulu.
mv2 kwabakwaDummies
U-Andrei. Ngeke nganeliseke uma umbhalo olandelayo ubonakala unzima kakhulu kuwe. Umsebenzi wami ukukuchazela ukuthi lesi siqeshana simayelana nani.2. Ngokuqondile ukuthi kungani isikwele nokuthi kungani sihlukanisa kabili.
Uyabona, i-mv ingumfutho, futhi amandla ayingxenye yomfutho. Kulula?
Ukuze udokotela wefiziksi akuphendule. Futhi ngi... Kodwa uma kwenzeka, njengesandulelo, isikhumbuzo sezinsuku zakudala. Lokhu sakufundiswa emabangeni aphansi (sasingakabikho isikole esiphakathi).
Amanani amabili alingana ngokuqondile uma, njengoba enye ikhula noma incipha, enye ikhula noma incipha, njalo ngesilinganiso esifanayo.
Isibonelo:
X 1 2 3 4 5 6 7 8 9
Mina 5 10 15 20 25 30 35 40 45
Kulokhu, u-Y uhlala emkhulu ngokuphindwe kahlanu kuno-X. Sisho lokho i-proportionality factor ngu-5. Ifomula echaza lesi silinganiso ithi y = 5x. Singadweba igrafu yomugqa oqondile y = 5x (1). Igrafu elinganiselwe yomugqa oqondile ingumugqa oqondile okhuphuka ngokufanayo. Ukwenyuka okulinganayo kokuhlukile okukodwa kuhambisana nokukhula okulinganayo kwesinye. Ngakho-ke, igama lezibalo eziningi lobudlelwano obunjalo yileli: ukuncika komugqa. Kodwa ngeke sikusebenzise.
1. Igrafu yomsebenzi y = 5x (ezinye izikali ezihambisana nezimbazo)
Manje ake siphendukele emandleni. Ayini amandla? Siyavuma ukuthi lolu uhlobo oluthile lwamandla afihliwe. “Anginawo amandla okuhlanza” acishe afane nokuthi “anginawo amandla okuhlanza.” Amandla angamandla acashile alele kithina ngisho nasezintweni, futhi kuhle ukuwathambisa ukuze asikhonze, futhi angabangeli ukubhujiswa. Sithola amandla, isibonelo, ngokushaja amabhethri.
Indlela yokulinganisa amandla? Kulula: isilinganiso somsebenzi angasenzela wona. Imaphi amayunithi esikala amandla? Njengomsebenzi nje. Kodwa ngezinjongo zalesi sihloko, sizokukala ku ... amamitha. Kanjani?! Sizobona.
Into elenga kubude obungu-h ngaphezu komkhathizwe ine amandla angaba khona. La mandla azokhishwa lapho sisika intambo lapho umzimba ulenga khona. Khona-ke uzowa futhi enze umsebenzi, ngisho noma nje umgodi phansi. Lapho into yethu indiza, inamandla e-kinetic, amandla okunyakaza ngokwawo.
Singavuma kalula ukuthi amandla angaba khona alingana nobude h. Ukuthwala umthwalo ufike kubude obungamahora ama-2 kuzosiqeda amandla ngokuphindwe kabili njengokuwuphakamisela kubude obungu-h. Lapho i-elevator isiyisa esitezi seshumi nanhlanu, izodla ugesi ophindwe kathathu kunangowesihlanu ... (emva kokubhala lo musho, ngabona ukuthi lokhu akulona iqiniso, ngoba i-elevator, ngaphezu kwabantu, nayo ithwala isisindo salo, futhi sikhulu - ukusindisa isibonelo, kufanele ushintshe i-elevator, isibonelo, nge-crane yokwakha). Okufanayo kusebenza ekulinganiseni kwamandla angaba khona kusisindo somzimba. Ukuthutha amathani angama-20 ukuya ekuphakameni kwamamitha ayi-10 kudinga ugesi ophindwe kabili njengamathani ayi-10 kuya ku-10 m. Lokhu kungavezwa ngefomula E ~ mh, lapho i-tilde (okungukuthi, uphawu ~) kuwuphawu lokulinganisa. Phinda kabili ubukhulu bese uphinda kabili ubude bulingana namandla aphindwe kane.
Ukunikeza umzimba amandla anamandla ngokuphakamisa ukuphakama okuthile bekungeke kwenzeke ukube bekungenjalo amandla adonsela phansi. Kungenxa yakhe ukuthi zonke izidumbu ziwela phansi (eMhlabeni). La mandla asebenza ukuze imizimba yamukele ukusheshisa njalo. Kusho ukuthini "ukusheshisa okuqhubekayo"? Lokhu kusho ukuthi umzimba owayo uyakhula kancane kancane - njengemoto isuka. Ihamba ngokushesha futhi ngokushesha, kodwa isheshisa ngesivinini esingaguquki. Maduze sizobona lokhu ngesibonelo.
Ake ngikukhumbuze ukuthi sisho ukusheshisa kokuwela mahhala g. Kungaba ngu-10 m/s2. Futhi, ungase uzibuze: iyini le yunithi engavamile - isikwele sesekhondi? Kodwa-ke, kufanele kuqondwe ngokuhlukile: njalo ngomzuzwana ijubane lomzimba owelayo likhuphuka ngamamitha angu-10 ngomzuzwana. Uma ngesinye isikhathi ihamba ngesivinini esingama-25 m/s, bese kuthi ngemva komzuzwana ibe nesivinini esingu-35 (m/s). Kuyacaca futhi ukuthi lapha sisho indikimba engakhathazeki kakhulu ngokumelana nomoya.
Manje sidinga ukuxazulula inkinga ye-arithmetic. Cabanga ngomzimba osanda kuchazwa, okuthi ngesikhathi esisodwa unejubane lika-25 m / s, futhi ngemva kwesibili 35. Kuzohamba kude kangakanani kulo mzuzwana? Inkinga ukuthi ijubane liyaguquguquka futhi kuyadingeka ukuze kubalwe ngendlela efanele. Kodwa-ke, izoqinisekisa lokho esikuzwayo ngokunembile: umphumela uzofana nowomzimba ohamba ngokufanayo ngesivinini esiphakathi: (25 + 35)/2 = 30 m/sec. - ngakho-ke 30 m.
Masidlulele kwenye iplanethi isikhashana, ngokusheshisa okuhlukile, sithi 2g. Kuyacaca ukuthi lapho sithola amandla anamandla aphindwe kabili ngokushesha - ngokukhuphula umzimba ukhuphuke ngokuphindwe kabili kunawo. Ngakho, amandla alingana nokusheshisa emhlabeni. Njengemodeli, sithatha ukusheshisa kokuwa kwamahhala. Ngakho-ke asiyazi impucuko ehlala eplanethini enamandla ahlukile wokukhanga. Lokhu kusiletha kufomula yamandla engaba khona: Е = uku.
Manje ake sisike intambo lapho silengise itshe le-mass m ubude obungu-h. Itshe liyawa. Uma ishaya phansi, izokwenza umsebenzi wayo - umbuzo wobunjiniyela, ukuthi singayisebenzisa kanjani ukuze sizuze.
Ake sidwebe igrafu: indikimba yesisindo m iwa phansi (labo abangithukayo ngenxa yegama elithi ngeke liwele, ngizophendula ngokuthi baqinisile, ngakho-ke ngibhale ukuthi liphansi!). Kuyoba khona ukungqubuzana kokumaka: uhlamvu m luzosho kokubili amamitha nobukhulu. Kodwa sizothola ukuthi nini. Manje ake sibheke igrafu engezansi futhi siphawule ngayo.
Abanye bazocabanga ukuthi amasu okusebenzisa izinombolo ahlakaniphile. Kodwa ake sihlole: uma umzimba usuka ngesivinini esingama-50 km / h, uzofinyelela ubude obuyi-125 m - okungukuthi, lapho ume khona isikhathi esifushane kakhulu, uzoba namandla angaba ngu-1250. m, futhi lokhu futhi yi-mV2/ 2. Uma sethula umzimba nge-40 km / h, izondiza ngo-80 m, futhi i-mv2/ 2. Manje cishe asingabazi ukuthi lokhu akukona nje ukuqondana. Sithole eyodwa ye Imithetho yokunyakaza kaNewton! Kwakudingeka kuphela ukusetha isilingo somcabango (oh, sorry, qala ngokuthola ukusheshisa kokuwa kwamahhala g - ngokusho kwenganekwane, uGalileo wenza lokhu lapho ewisa izinto embhoshongweni wasePisa, ngisho nangemva kwalokho ijika) futhi okubaluleke kakhulu: babe nolwazi lwezinombolo. Kholwa ukuthi iNkosi uNkulunkulu enhle yadala umhlaba ngokulandela imithetho (okungenzeka ukuthi waziqambela yona). Mhlawumbe wayezitshela ukuthi, "Hawu ngizoshaya imithetho ukuze bahlukaniswe kabili." Leyo ngxenye, iningi lezinto ezingaguquki zomzimba zixakile ngendlela emangalisayo kangangokuthi ungasola uMdali wamahlaya. Lokhu kuyasebenza nasezibalweni, kodwa hhayi ngakho namuhla.
Cishe eminyakeni eyishumi nambili edlule, eTatras, abaqwali bacela usizo kolunye lwezindonga zaseMorskie Oko. Kwakungu February, kubanda, izinsuku ezimfushane, isimo sezulu esibi. Abatakuli bafika kubo emini kuphela ngakusasa. Abaqwali sebevele begodola, belambile, sebekhathele. Umhlengi wanikeza owokuqala i-thermos yetiye elishisayo. "Ngoshukela?" kubuza umqwali ngephimbo elingazwakali. "Yebo, ngoshukela, amavithamini kanye ne-booster circulatory." “Ngiyabonga, angiphuzi noshukela!” - waphendula umqwali walahlekelwa ukwazi. Mhlawumbe, umshayeli wethu wesithuthuthu naye wabonisa ukuhleka okufanayo, okufanelekile. Kodwa ihlaya laliyojula ukube wayebubule, ake sithi: "O, uma kungenjalo lesi sikwele!".
Ngokwalokho okushiwo ifomula, ubudlelwano E = mv2/ 2? Yini ebangela "isikwele"? Buyini ubungqabavu bobudlelwano "besikwele"? Ukuthi, ngokwesibonelo, ukuphinda kabili imbangela kukhiqiza umphumela ophindwe kane; kathathu - izikhathi eziyisishiyagalolunye, izikhathi ezine - izikhathi eziyishumi nesithupha. Amandla esinawo uma sihamba nge-20 km/h aphansi ngokuphindwe kane kunama-40, futhi angaphansi ngokuphindwe kashumi nesithupha kunama-80! Futhi ngokuvamile, cabanga ngemiphumela yokushayisana ngesivinini esingama-20 km / h. nemiphumela yokushayisana kuka-80 km/h. Ngaphandle kwanoma yisiphi isifanekiso, ungabona ukuthi kukhulu, kukhudlwana kakhulu. Isilinganiso semiphumela siyakhuphuka maqondana nesivinini, futhi ukuhlukaniswa ngokubili kuthambisa lokhu kancane.
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Aphelile amaholide. Sekuyiminyaka eminingana ngibhala izihloko. Manje... anginawo amandla. Kuzodingeka ngibhale mayelana nezinguquko kwezemfundo, nazo ezinezinhlangothi ezinhle, kodwa isinqumo sathathwa ngaphandle kwesihloko ngabantu ababefaneleka lokho engiyikho ku-ballet (ngikhuluphele kakhulu futhi ngineminyaka engaphezu kuka-70 ubudala. ).
Kodwa-ke, njengokungathi ngisemsebenzini, ngizobhekisela kokunye ukubonakaliswa kokungazi okuyisisekelo phakathi kwezintatheli. Kuyavunywa, akukho lutho oluqhathaniswa nomlobi wezindaba wase-Olsztyn owanikela ngesihloko eside endabeni yokukhwabanisa kwabathengi ngabakhiqizi. Nokho, intatheli yabhala, okuqukethwe kwamafutha kwakuboniswe ephaketheni lebhotela njengephesenti, kodwa akuzange kuchazwe ukuthi ngabe ikhilogremu ngayinye noma ikhiyubhu ngayinye ...
Ukunemba okubhalwe yintatheli u-A.B. (ama-initials aqanjiwe) e-Tygodnik Powszechny yangoJulayi 30 kulo nyaka, izacile. Wathi, ngokocwaningo lwe-CBOS, amaphesenti angu-48 abantu abazibheka njengenkolo kakhulu athatha isimo sengqondo sika-X (kungakhathaliseki ukuthi siyini, akunandaba), kanye nama-41% alabo abahlanganyela emikhubeni yenkolo izikhathi eziningana. ukwesekwa kwesonto X. Lokhu kusho, umlobi ubhala, ukuthi ngaphezu kwezingxenye ezimbili kwezinhlanu zamaKatolika akhuthele kakhulu awaboni u-X. Ngazama isikhathi eside ukuthola ukuthi umlobi uthole kuphi lezi zingxenye ezimbili nesihlanu, futhi ... Angiqondi. Alikho iphutha elisemthethweni, njengoba ngempela, uma sikhuluma ngezibalo, ngaphezu kwezingxenye ezimbili kwezinhlanu zabaphenduli baphikisana no-X. Ungasho nje ukuthi ngaphezu kwesigamu (100 - 48 = 52).
