Fahimtar Dokokin Newton na Motsi: Jagora Mai Cikakke ga Masu Farawa

Newton's Laws of Motion sune tushen tushen injiniya na gargajiya, suna ba da ƙa'idodin da ke kula da yadda abubuwa ke motsawa lokacin da makamai ke aiki a kansu. Sir Isaac Newton ya tsara su a cikin karni na 17, waɗannan dokokin guda uku suna bayanin komai daga dalilin da yasa littafi ya kasance a kan teburin zuwa yadda roket ke ƙaddamar da sararin samaniya. Ko kai ɗalibi ne da ke ɗaukar darasin ilimin lissafi na farko ko kuma ƙwararre wanda ke neman sabunta ilimin tushe, masanin waɗannan ƙa'idodin yana da mahimmanci don fahimtar duniyar zahiri. A cikin wannan jagorar, za mu karya kowane doka a cikin harshe mai sauƙi, bincika misalai na duniyar gaske, da kuma nuna dalilin da ya sa fahimtar Newton ta kasance mai mahimmanci a cikin kimiyya da injiniya ta zamani.

Labarin Tarihi: Yadda Newton Ya Canja Fisik

Kafin Newton, ra'ayin da ya fi rinjaye game da motsi ya fito ne daga Aristotle, wanda ya yi imanin cewa abubuwa a zahiri sun tsaya a hutawa sai dai idan wata karfi ta ci gaba da tura su. Galileo Galilei ya kalubalanci wannan ra'ayin tare da gwaji a kan jirage masu gangara, yana lura da cewa abubuwa masu motsi suna da saurin kasancewa cikin motsi idan aka rage tsagewa. Newton ya hada waɗannan lura da aikinsa a cikin Philosophiæ Naturalis Principia Mathematica (FLT: 1) (1687), inda ya buga dokoki uku na motsi tare da dokar janareta ta duniya.

Newton ya ba da gudummawa mai juyin juya hali saboda ya samar da tsari mai yawa, mai tsinkaye don motsi. Maimakon bayyana motsi a cikin inganci, dokokinsa sun ba masana kimiyya damar yin lissafi daidai yadda wata karfi zata canza saurin abu. Wannan hanyar lissafi ta kafa tushe ga juyin juya halin masana'antu, kimiyyar zamani, har ma da binciken sararin samaniya. Kuna iya karanta ƙarin game da rayuwar Newton da hanyoyinsa a Stanford Encyclopedia of Philosophy ko bincika kwaikwayo mai ma'amala a FLT:4PhET Interactive Simulations.

Dokar Newton ta Farko: Dokar Inertia

Dokar farko ta Newton ta ce: ] Wani abu a hutawa ya kasance a hutawa, kuma wani abu mai motsi ya kasance a motsi tare da sauri iri ɗaya kuma a cikin hanya iri ɗaya, sai dai idan an yi aiki akan shi ta hanyar ƙarfin waje mara daidaituwa.

Abin da Rashin ƙarfi Yake Nufi Gaskiya

A cikin kwarewar yau da kullun, muna ganin abubuwa suna jinkirtawa da tsayawa koyaushe: kwalban da ke juyawa ta tsaya saboda taƙaitawa, littafi mai zamewa akan tebur ya tsaya saboda juriya ta iska da taƙaitawar farfajiyar. Amma Dokar Farko ta gaya mana cewa idan za a iya cire duk ƙarfin waje (taƙaitawa, juriya, nauyi, da sauransu), abu zai ci gaba da motsi har abada a madaidaiciyar layi a saurin daidaitawa. Wannan shine kyakkyawan ra'ayi na ra'ayi wanda ke nuna halayyar asali ta abu.

Inertia yana da alaƙa kai tsaye da taro. mafi yawan nauyin abu, mafi yawan inertia yana da shi, kuma ya fi wuya a fara motsi ko dakatar da shi da zarar ya motsa. Alal misali, yana da sauƙin tura keke fiye da mota saboda mota tana da yawa mafi girman inertia.

Misalai na Dokar Farko na Yau da kullum

  • Sa'ad da mota ta tsaya kwatsam, jikinka yana ci gaba da motsawa gaba saboda rashin ƙarfi.
  • Aikin tebur: Idan ka ja tebur da sauri, jita-jita suna kasancewa a wurin saboda ƙarfin jujjuyawar bai sami lokacin yin aiki ba.
  • Rashin daidaituwa a bas: Lokacin da bas ya hanzarta hanzarta, jikinka yana da saurin zama a kwanciyar hankali dangane da ƙasa, yana sa ka yi makilci baya.

Abubuwa Masu Muhimmanci Daga Dokar Farko

  • Abubuwan da ba su da ƙarfi don ci gaba da motsi suna buƙatar ƙarfi don canza motsin su.
  • Inertia ba karfi ba ne; dukiya ce ta abu.
  • Dokar ta bayyana tsarin tunani na inertial a cikin tsarin da doka ta kasance gaskiya. A cikin tsarin hanzari (kamar carousel mai juyawa), ana bayyana ƙarfin tunani.

Dokar Newton ta Biyu ta Motsi: Dokar Hanzari

Newton's Dokar Biyu ta samar da dangantakar lissafi tsakanin karfi, taro, da hanzari: F Fnet = m × a. A nan, Fnet shine ƙarfin waje mai aiki akan abu (wanda aka auna a cikin Newton, N), m shine nauyin abu (kg), kuma a shine hanzarinta (m/s2). Wannan dokar ta gaya mana daidai yadda wani abu zai hanzarta, jinkirta, ko canza shugabanci lokacin da aka yi amfani da karfi.

Yadda Za a Ƙyale Tsarin

  • F (FLT: 0) ne mai ɗaukar hoto na dukkan sojojin da ke aiki akan abu. Idan makamai da yawa suna turawa a cikin hanyoyi daban-daban, ƙarfin net yana ƙayyade motsi.
  • FLT: 0 m FLT: 1 shine nauyin ƙarfin ƙarfin abu a matsayin ma'auni na yadda yake tsayayya da hanzari.
  • a shine hanzari, wanda ke nunawa a cikin hanya ɗaya da ƙarfin net.

Ka lura cewa dokar ta ce hanzari ya kasance daidai da ƙarfin net: ninka ƙarfin, kuma ka ninka hanzari (don wannan ƙarfin).

Yadda Za a Yi Amfani da Su

  • Kayan motar: Injiniyoyi suna amfani da F = ma don lissafin ƙarfin injin da ake buƙata don hanzarta mota daga 0 zuwa 60 mph a cikin wani lokaci.
  • Kayan wasa: Mai jefa kwando yana amfani da karfi ga kwallon a kan gajeren nesa. Ta hanyar kara karfi (mafi karfi hannu) ko rage taro (ƙarfi mai haske), hanzarisaboda haka saurin karsheya karu.
  • Airbags: A lokacin haɗuwa, airbag yana turawa don ƙara lokacin da aka yi amfani da ƙarfin, rage hanzari (kuma saboda haka ƙarfin) akan mai hawa. Wannan aikace-aikacen kai tsaye ne na F = ma: tsawon lokaci yana nufin ƙaramin matsakaicin ƙarfi don canjin ƙarfi iri ɗaya.
  • Abubuwan da ke faduwa: Nauyin nauyi yana ba da karfi mai saurin sauka (FLT:2mg), don haka duk abubuwan da ke kusa da saman duniya suna hanzarta a 9.8 m / s2 ba tare da la'akari da nauyin ba, ba tare da la'akari da juriya ta iska ba. Wannan shine dalilin da ya sa gashin da maciji suka fadi tare a kan wata.

Misali na Ƙididdiga na Al'ada

A ce ka tura akwatin 10 kg tare da ƙarfin zurfin 50 N. Hanzari = F/m = 50 N / 10 kg = 5 m/s. Idan ka ninka ƙarfin zuwa 100 N, hanzari ya zama 10 m/s. Idan ka riƙe ƙarfin a 50 N amma ka ninka nauyin zuwa 20 kg, hanzari ya ragu zuwa 2.5 m/s2.

Don zurfin ilimin lissafi da kayan aikin kwaikwayo, duba jagorar Khan Academy zuwa Dokar Newton ta Biyu.

Newton's Dokar Tafiya ta Uku: Dokar Aiki da Reaction

Newton's Dokar Uku ta bayyana: Ga kowane aiki, akwai daidaito da kuma akasin amsa. Wannan yana nufin cewa karfi koyaushe suna faruwa a nau'i-nau'i. Lokacin da abu A ya yi amfani da karfi akan abu B, abu B a lokaci guda yana amfani da karfi mai girman daidai da kuma juyawa a kan abu A.

Bayyana Ma'auni na Aiki da Halin

Yana da mahimmanci a fahimci cewa sojojin biyu a cikin nau'in aiki da aiki suna aiki akan abubuwa daban-daban. Ba sa soke juna saboda suna shafar jikin daban. Misali, lokacin da ka tura ganuwar, ganuwar tana turawa baya da karfi iri ɗaya.

Misalan da Suka Faru a Duniyarmu

  • Tafiya: Kafarka tana turawa baya a ƙasa; ƙasa tana turawa gaba a ƙafafunka. Wannan turawa gaba tana tura ka.
  • Yin iyo: Kuna tura ruwa baya; ruwa yana tura ku gaba.
  • Tirgar roka: Raketa tana fitar da gas din fitarwa zuwa kasa; gas din fitarwa yana tura roket zuwa sama. Wannan yana aiki a cikin iska ta sararin samaniya saboda babu buƙatar iska ta waje.
  • Kicka ball: Kafa ta yi amfani da karfi ga kwallon, tana tura ta gaba; ball ya yi amfani da karfi daidai da baya a ƙafafunku (wanda kuke ji kamar ƙugiya).

Me Ya Sa Ma'aurata Ba Sa Cancellate

Yawancin ɗalibai suna tunanin cewa idan kowane aiki yana da daidai akasin amsa, to duk ƙarfin zai soke kuma babu abin da zai iya hanzarta. Kuskuren yana cikin manta cewa sojojin biyu suna aiki akan abubuwa daban-daban.

Ra'ayoyi da Bayani Masu Yawa

Ana fahimtar dokokin Newton sau da yawa saboda littattafan koyarwa suna sauƙaƙa su ko kuma saboda kwarewarmu ta yau da kullun ta ƙunshi ƙarfi kamar taƙaitawa da juriya ta iska waɗanda ke ɓoye halayyar da aka yi niyya. Ga wasu tatsuniyoyi masu ɗorewa, da aka gyara:

MisconceptionCorrection
Objects in motion need a force to keep moving. According to the First Law, objects maintain their velocity unless acted on by a net external force. Friction and air resistance are forces that slow them down.
Heavy objects fall faster than light ones. In a vacuum, all objects fall at the same acceleration g because the gravitational force (mg) is proportional to mass, so the masses cancel in F=ma. Air resistance can cause different rates, but that’s a separate force.
Action and reaction forces cancel out, so no net motion is possible. They act on different objects, so they don’t cancel for a single body. The net force on each object determines that object’s acceleration.
Newton’s laws are only true on Earth. They apply anywhere in the universe, though they break down at very high speeds (near light speed) or very strong gravity (requiring relativity) and at atomic scales (requiring quantum mechanics).

Me Ya Sa Dokokin Newton Suna da Muhimmanci Har A Yau

Dokokin Newton ba kawai abubuwan tarihi bane. Suna zama tushen yawancin fannonin injiniya, daga nazarin tsari zuwa robotics. Lokacin da kake tsara gada, kuna lissafin ƙarfin kowane tsutsa ta amfani da dokokin Newton. Lokacin da kake tsara kwaikwayo don wasan bidiyo, injin kimiyyar lissafi yawanci yana amfani da injin Newton. Har ma hukumomin sararin samaniya suna amfani da waɗannan dokokin don tsara hanyoyin jirgin sama, kodayake suna ƙara gyaran ƙayyadaddun bayanai don tsananin daidaito.

Bugu da ƙari, dokokin Newton sune ƙofar zuwa zurfin ilimin lissafi. Suna kai tsaye zuwa ka'idodin kiyaye motsi (wanda ya samo asali daga Dokar Uku) da kiyaye makamashi (ta hanyar ka'idar aiki-makamashi, wanda ya samo asali daga Dokar Biyu). Fahimtar su yana sauƙaƙa fahimtar wutar lantarki, thermodynamics, har ma da abubuwan da suka shafi yanayin yanayin.

Ƙuntatawa: Idan Dokar Newton Ba Ta Amfani

Duk da yake suna da iko sosai, dokokin Newton ba su da kyau a kowane yanayi.

  • Saurin gudu: Lokacin da abubuwa suka kusanci saurin haske, ana buƙatar ka'idar Einstein ta musamman.
  • Filin nauyi mai ƙarfi: A kusa da baƙin ramuka ko a cikin dukan sararin samaniya a kan manyan sikelin, lissafin zumunta na gaba ɗaya ya bayyana nauyi azaman lankwasawa na sararin samaniya.
  • A ƙananan sikelin: A matakin atomatik da na subatomic, injin quantum yana sarrafa hali. Injin Newton bai bayyana abubuwan da ke faruwa ba kamar su lantarki orbitals da kuma hanyoyin da ake amfani da su.

Duk da haka, ga mafi yawan abubuwan yau da kullum - motoci, wasanni, gine-gine, tsarin yanayi, har ma da tauraron dan adam - dokokin Newton sun kasance daidai kuma sun isa.

Takaitaccen Dokoki Uku

  1. Dokar farko (Inertia): (FLT: 1) Abubuwa suna tsayayya da canje-canje a motsi. Jiki a hutawa yana kasancewa a hutawa; jiki a cikin motsi iri ɗaya yana kasancewa a motsi sai dai idan wata ƙarfin waje ta yi aiki a kanta.
  2. Dokar ta biyu (Force & Acceleration): (FLT: 1) Ƙarfin ƙarfin a kan wani abu ya yi daidai da nauyin abu da aka ninka ta hanyar hanzarta shi (F = m × a). Wannan dokar ta ƙididdige yadda karfi ke haifar da canje-canje a motsi.
  3. Dokar uku (ActionReaction):FTL:1]] Ga kowane karfi da abu A ya yi amfani da shi akan abu B, abu B yana amfani da karfi iri ɗaya da kuma akasin haka akan abu A. Waɗannan ƙarfin suna aiki akan jikin daban-daban.

Ko kana da aikin gida, ko kuma kana da wata na'ura, ko kuma kana son sanin dalilin da ya sa kofi yake zubar da jini sa'ad da ka fasa, dokokin Newton suna ba da bayani mai kyau.

Don ƙarin karatu, Cibiyar Nazarin Glenn ta NASA tana da kyakkyawan bayani ga masu farawa, kuma shigarwar Britannica na FLT:3 tana ba da zurfin tarihi.