Cov txheej txheem:

Peb kawm physics thiab qhia cov me nyuam yam tsis tau tawm hauv chav ua noj
Peb kawm physics thiab qhia cov me nyuam yam tsis tau tawm hauv chav ua noj

Video: Peb kawm physics thiab qhia cov me nyuam yam tsis tau tawm hauv chav ua noj

Video: Peb kawm physics thiab qhia cov me nyuam yam tsis tau tawm hauv chav ua noj
Video: Saib Mis paub Poj niam (hluas nkauj) tus yam ntxwv lub siab 2024, Tej zaum
Anonim

Peb siv 1-2 teev hauv chav ua noj txhua hnub. Ib tug tsawg, ib tug ntau. Hais tias, peb tsis tshua xav txog lub cev tshwm sim thaum peb noj tshais, pluas su lossis noj hmo. Tab sis yuav tsis muaj ntau dua concentration ntawm lawv nyob rau hauv niaj hnub mob tshaj nyob rau hauv lub chav ua noj, nyob rau hauv lub tsev apartment. Lub sijhawm zoo los piav txog physics rau menyuam yaus!

Diffusion
Diffusion

1. Kev nthuav dav

Peb niaj hnub ntsib nrog qhov tshwm sim hauv chav ua noj. Nws lub npe yog muab los ntawm Latin diffusio - kev sib cuam tshuam, dispersal, faib.

Qhov no yog cov txheej txheem ntawm kev sib nrig sib nkag mus ntawm molecules los yog atoms ntawm ob yam khoom nyob ib sab. Tus nqi diffusion yog proportional rau qhov chaw hla ntu ntawm lub cev (ntim), thiab qhov sib txawv ntawm cov concentrations, qhov kub thiab txias ntawm cov khoom sib xyaw. Yog tias muaj qhov sib txawv ntawm qhov kub thiab txias, ces nws teev cov kev taw qhia ntawm kev nthuav tawm (gradient) - los ntawm kub mus rau txias. Raws li qhov tshwm sim, kev hloov pauv hloov pauv ntawm cov concentrations ntawm molecules lossis atoms tshwm sim.

Qhov tshwm sim no tuaj yeem pom hauv chav ua noj thaum cov ntxhiab tsw kis. Ua tsaug rau qhov diffusion ntawm cov pa roj, zaum hauv lwm chav, koj tuaj yeem nkag siab tias yog dab tsi ua noj. Raws li koj paub, cov pa roj carbon monoxide tsis muaj ntxhiab tsw thiab muaj cov tshuaj ntxiv ntxiv rau nws kom nws yooj yim dua los kuaj xyuas cov pa tawm hauv tsev.

Ib qho tshuaj tsw qab xws li ethyl mercaptan ntxiv cov ntxhiab tsw ntxhiab. Yog tias lub tshuab hluav taws xob tsis pom thawj zaug, peb tuaj yeem hnov cov ntxhiab tsw tshwj xeeb, uas peb paub txij thaum yau raws li qhov tsis hnov tsw ntawm cov pa hauv tsev.

Thiab yog tias koj pov cov nplej los yog ib lub hnab ntim rau hauv dej npau thiab tsis do, koj tuaj yeem pom tias cov tshuaj yej infusion kis tau li cas hauv cov dej ntshiab.

Qhov no yog qhov diffusion ntawm cov kua. Ib qho piv txwv ntawm diffusion nyob rau hauv ib qho khoom yuav yog salting ntawm lws suav, dib, nceb, los yog cabbage. Cov ntsev ntsev hauv dej tawg mus rau hauv Na thiab Cl ions, uas, txav mus rau chaotically, nkag mus ntawm cov molecules ntawm cov khoom nyob rau hauv muaj pes tsawg leeg ntawm zaub los yog nceb.

Hloov ntawm lub xeev ntawm aggregation
Hloov ntawm lub xeev ntawm aggregation

2. Kev hloov ntawm lub xeev ntawm kev sib sau

Ob peb ntawm peb pom tias nyob rau hauv ib khob dej sab laug, tom qab ob peb hnub, tib feem ntawm cov dej evaporates ntawm chav tsev kub li thaum boiling rau 1-2 feeb. Thiab thaum peb khov zaub mov lossis dej rau cov dej khov hauv lub tub yees, peb tsis xav txog qhov no tshwm sim li cas.

Lub caij no, cov phenomena feem ntau thiab ntau hauv chav ua noj tau piav qhia yooj yim. Cov kua muaj qhov nruab nrab nruab nrab ntawm cov khoom thiab cov pa.

Ntawm qhov kub thiab txias uas tsis yog boiling los yog khov, lub zog ntawm attraction ntawm molecules nyob rau hauv cov kua yog tsis muaj zog los yog qaug zog raws li nyob rau hauv cov khib nyiab thiab gases. Yog li ntawd, piv txwv li, tsuas yog tau txais lub zog (los ntawm lub hnub lub rays, huab cua molecules nyob rau hauv chav tsev kub), cov kua molecules los ntawm qhib qhov chaw maj mam dhau mus rau lub gas theem, tsim ib tug vapor siab saum cov kua nto.

Tus nqi evaporation nce nrog qhov nce hauv thaj tsam ntawm cov kua dej, qhov nce hauv qhov kub thiab txias, thiab txo qis rau sab nraud. Yog hais tias qhov kub thiab txias, ces lub vapor siab ntawm cov kua no mus txog rau sab nraud siab. Qhov kub ntawm qhov no tshwm sim yog hu ua lub boiling point. Lub boiling point txo nrog txo sab nraud siab. Yog li ntawd, nyob rau hauv roob roob, dej boils sai.

Hloov pauv, thaum qhov kub thiab txias poob, cov dej molecules poob lawv lub zog kinetic rau qib ntawm lub zog ntawm kev nyiam ntawm lawv tus kheej. Lawv tsis txav mus rau chaotically, uas tso cai rau tsim ib tug siv lead ua lattice zoo li cov khib nyiab. Qhov kub ntawm 0 ° C thaum qhov no tshwm sim yog hu ua qhov chaw khov dej.

Thaum khov, dej nthuav dav. Ntau tus neeg tuaj yeem paub txog qhov tshwm sim no thaum lawv muab lub raj mis yas nrog haus dej hauv lub freezer kom txias sai thiab tsis nco qab txog nws, thiab tom qab ntawd lub raj mis tawg. Thaum txias rau qhov kub ntawm 4 ° C, qhov nce ntawm qhov ntom ntawm cov dej yog thawj zaug pom, thaum nws qhov siab tshaj plaws thiab qhov ntim tsawg kawg nkaus tau mus txog. Tom qab ntawd, ntawm qhov kub ntawm 4 mus rau 0 ° C, kev hloov pauv ntawm cov ntawv cog lus hauv cov dej molecule tshwm sim, thiab nws cov qauv yuav tsis ntom.

Ntawm qhov kub ntawm 0 ° C, cov kua theem ntawm cov dej hloov mus rau cov khoom. Tom qab cov dej khov tag thiab hloov mus rau hauv dej khov, nws qhov ntim loj hlob los ntawm 8, 4%, uas ua rau tawg ntawm lub raj mis yas. Cov ntsiab lus kua hauv ntau cov khoom yog tsawg, yog li lawv tsis nce hauv ntim thiaj li pom tau thaum khov.

Absorption thiab adsorption
Absorption thiab adsorption

3. Absorption thiab adsorption

Ob qhov yuav luag sib cais tsis sib xws, hu ua los ntawm Latin sorbeo (kom nqus tau), tau pom, piv txwv li, thaum cua sov dej hauv lub lauj kaub lossis saucepan. Cov roj uas tsis muaj tshuaj lom neeg ua rau cov kua tuaj yeem nqus tau los ntawm kev sib cuag nrog nws. Qhov tshwm sim no hu ua absorption.

Thaum cov roj yog absorbed los ntawm cov khoom nplua-grained los yog ntxeem tau lub cev, feem ntau ntawm lawv densely accumulates thiab khaws cia nyob rau saum npoo ntawm pores los yog nplej thiab tsis muab faib thoob plaws hauv lub ntim. Hauv qhov no, cov txheej txheem hu ua adsorption. Cov xwm txheej no tuaj yeem pom thaum cov dej kub npau npau - npuas sib cais los ntawm cov phab ntsa ntawm lub lauj kaub lossis lub lauj kaub thaum rhuab.

Cov pa tawm ntawm dej muaj 63% nitrogen thiab 36% oxygen. Feem ntau, atmospheric cua muaj 78% nitrogen thiab 21% oxygen.

Lub rooj ntsev nyob rau hauv ib lub thawv uncovered tuaj yeem ntub vim nws cov khoom hygroscopic - nqus dej vapor los ntawm huab cua. Thiab ci dej qab zib ua ib qho adsorbent thaum muab tso rau hauv lub tub yees kom tshem tawm tsw.

Archimedes txoj cai
Archimedes txoj cai

4. Kev tshwm sim ntawm Archimedes txoj cai

Thaum peb npaj ua noj nqaij qaib, peb sau lub lauj kaub nrog dej li ib nrab lossis ¾, nyob ntawm qhov loj ntawm cov nqaij qaib. Los ntawm immersing lub carcass nyob rau hauv ib lub lauj kaub dej, peb pom tias qhov hnyav ntawm cov nqaij qaib nyob rau hauv cov dej yog noticeably txo, thiab cov dej nce mus rau lub npoo ntawm lub lauj kaub.

Qhov tshwm sim no tau piav qhia los ntawm buoyancy force lossis Archimedes txoj cai. Hauv qhov no, lub zog buoyant ua rau lub cev rau hauv cov kua, sib npaug ntawm qhov hnyav ntawm cov kua hauv qhov ntim ntawm submerged ib feem ntawm lub cev. Lub zog no hu ua lub zog ntawm Archimedes, raws li txoj cai nws tus kheej, uas piav txog qhov tshwm sim no.

Ntog nro
Ntog nro

5. Nto nro

Ntau tus neeg nco qab qhov kev sim nrog cov yeeb yaj kiab ntawm cov kua dej, uas tau qhia hauv physics hauv tsev kawm ntawv. Ib tug me me hlau ncej nrog ib sab movable tau dipped nyob rau hauv xab npum dej thiab ces rub tawm. Lub zog ntawm qhov nro nyob rau hauv zaj duab xis tsim raws li perimeter lifted qis movable ib feem ntawm tus ncej. Txhawm rau kom nws txav tsis tau, qhov hnyav tau raug tshem tawm ntawm nws thaum qhov kev sim rov ua dua.

Qhov tshwm sim no tuaj yeem pom hauv lub colander - tom qab siv, dej tseem nyob hauv qhov hauv qab ntawm cov khoom siv hauv chav ua noj. Tib qhov tshwm sim tuaj yeem pom tom qab ntxuav cov diav rawg - kuj tseem muaj cov dej ntws tawm ntawm sab hauv nruab nrab ntawm qee cov hniav.

Lub physics ntawm cov kua piav qhia qhov tshwm sim no raws li hauv qab no: cov kua molecules yog li nyob ze rau ib leeg, uas lub zog ntawm attraction ntawm lawv tsim nto nro nyob rau hauv lub dav hlau ntawm qhov chaw dawb. Yog hais tias lub zog ntawm attraction ntawm cov dej molecules ntawm cov kua zaj duab xis yog tsis muaj zog tshaj lub zog ntawm attraction rau saum npoo ntawm lub colander, ces cov zaj duab xis dej yuav tawg.

Tsis tas li ntawd, lub zog ntawm qhov nro yog pom tau thaum peb ncuav cov nplej los yog peas, taum rau hauv saucepan nrog dej, los yog ntxiv cov nplej ntawm cov kua txob. Qee cov nplej yuav nyob twj ywm ntawm cov dej, thaum feem ntau yuav nkag mus rau hauv qab hauv qab qhov hnyav ntawm tus so. Yog tias koj nias maj mam rau ntawm cov nplej uas ntab nrog lub ntsis ntawm koj tus ntiv tes lossis rab diav, lawv yuav kov yeej qhov nro ntawm cov dej thiab tso rau hauv qab.

Wetting thiab kis
Wetting thiab kis

6. Kev ntub dej thiab sib kis

Cov kua ua kua tuaj yeem tsim cov stains me me rau ntawm lub qhov cub roj, thiab ib lub pas dej ntawm lub rooj. Qhov tshaj plaws yog tias cov kua molecules nyob rau hauv thawj rooj plaub yog attracted rau ib leeg ntau dua rau saum npoo ntawm lub phaj, qhov twg muaj ib tug fatty zaj duab xis tsis wetted los ntawm dej, thiab nyob rau hauv ib tug huv lub rooj qhov attraction ntawm cov dej molecules rau lub molecules ntawm dej. lub rooj saum npoo yog siab tshaj qhov attraction ntawm dej molecules rau ib leeg. Raws li qhov tshwm sim, lub pas dej sib kis.

Qhov tshwm sim no kuj muaj feem xyuam rau lub cev ntawm cov kua thiab muaj feem xyuam rau qhov nro ntawm qhov chaw. Raws li koj paub, xab npum npuas los yog kua tee dej muaj ib tug kheej kheej zoo vim lub zog nro saum npoo.

Nyob rau hauv ib tug tee dej, cov kua molecules yog attracted rau ib leeg ntau zog tshaj cov roj molecules, thiab zoo li mus rau sab hauv ntawm cov kua tee dej, txo nws cov deg cheeb tsam. Tab sis, yog tias muaj cov khoom ntub dej, ces ib feem ntawm qhov poob ntawm kev sib cuag yog stretched raws nws, vim hais tias cov molecules ntawm cov khoom nyiam cov molecules ntawm cov kua, thiab lub zog no tshaj lub zog ntawm attraction ntawm lub molecules ntawm cov kua..

Lub degree ntawm ntub dej thiab kis mus rau ib tug khoom nto yuav nyob ntawm seb lub zog twg ntau dua - lub zog ntawm attraction ntawm molecules ntawm ib tug kua thiab molecules ntawm ib tug khoom ntawm lawv tus kheej los yog lub zog ntawm attraction ntawm molecules nyob rau hauv cov kua.

Txij li xyoo 1938, qhov tshwm sim ntawm lub cev no tau siv dav hauv kev lag luam, hauv kev tsim cov khoom siv hauv tsev, thaum Teflon (polytetrafluoroethylene) cov khoom raug tsim los hauv DuPont qhov chaw kuaj.

Nws cov khoom yog siv tsis tau tsuas yog nyob rau hauv kev tsim khoom ntawm cov khoom siv uas tsis yog-stick cookware, tab sis kuj nyob rau hauv kev tsim cov dej tsis zoo, dej-repellent fabrics thiab coatings rau khaub ncaws thiab khau. Teflon tau lees paub los ntawm Guinness Phau Ntawv Cov Ntaub Ntawv raws li lub ntiaj teb cov khoom npluas tshaj plaws. Nws muaj tsawg heev nto nro thiab adhesion (so), nws tsis yog wetted nrog dej, roj los yog ntau organic solvents.

Thermal conductivity
Thermal conductivity

7. Thermal conductivity

Ib qho tshwm sim feem ntau hauv chav ua noj uas peb tuaj yeem soj ntsuam yog qhov cua sov ntawm lub lauj kaub los yog dej hauv saucepan. Thermal conductivity yog hloov cov cua sov los ntawm kev txav ntawm cov khoom thaum muaj qhov sib txawv (gradient) hauv qhov kub thiab txias. Ntawm cov hom thermal conductivity, kuj muaj convection.

Nyob rau hauv cov ntaub ntawv ntawm cov khoom zoo tib yam, cov thermal conductivity ntawm cov kua yog tsawg tshaj li cov khib nyiab, thiab siab dua li cov roj. Lub thermal conductivity ntawm gases thiab hlau nce nrog nce kub, thiab cov kua dej txo. Peb niaj hnub ntsib nrog convection, txawm tias peb do kua zaub los yog tshuaj yej nrog ib rab diav, los yog qhib lub qhov rais, los yog qhib lub qhov cua kom ventilate lub chav ua noj.

Convection - los ntawm Latin convectiō (hloov) - ib hom kev hloov hluav taws xob thaum lub zog sab hauv ntawm cov roj lossis cov kua xa tawm los ntawm cov dav hlau thiab cov kwj deg. Paub qhov txawv ntawm ntuj convection thiab yuam. Hauv thawj kis, cov khaubncaws sab nraud povtseg ntawm cov kua lossis cua yog lawv tus kheej sib xyaw thaum cua sov lossis txias. Thiab nyob rau hauv rooj plaub thib ob, muaj kev sib xyaw ua ke ntawm cov kua lossis roj - nrog rab diav, kiv cua lossis lwm txoj hauv kev.

Electromagnetic hluav taws xob
Electromagnetic hluav taws xob

8. hluav taws xob hluav taws xob

Lub qhov cub microwave qee zaum hu ua lub qhov cub microwave, lossis qhov cub microwave. Lub ntsiab tseem ceeb ntawm txhua qhov cub microwave yog magnetron, uas hloov hluav taws xob hluav taws xob mus rau hauv microwave electromagnetic hluav taws xob nrog lub zaus txog li 2.45 gigahertz (GHz). Radiation heats zaub mov los ntawm kev cuam tshuam nrog nws cov molecules.

Cov khoom lag luam muaj cov dipole molecules uas muaj cov hluav taws xob zoo thiab cov nqi tsis zoo ntawm lawv qhov sib txawv.

Cov no yog cov roj molecules, qab zib, tab sis feem ntau ntawm tag nrho cov dipole molecules nyob rau hauv dej, uas muaj nyob rau hauv yuav luag txhua yam khoom. Lub microwave teb, tas li hloov nws cov kev taw qhia, ua rau cov molecules vibrate nrog lub siab zaus, uas nyob rau hauv raws li txoj kab ntawm lub zog kom tag nrho cov zoo nqi ntawm cov molecules "saib" nyob rau hauv ib qho kev taw qhia los yog lwm yam. Molecular kev sib txhuam tshwm sim, lub zog raug tso tawm, uas ua kom sov cov zaub mov.

Induction
Induction

9. Induction

Hauv chav ua noj, koj tuaj yeem nrhiav induction cookers nce ntxiv, uas yog raws li qhov tshwm sim no. English physicist Michael Faraday nrhiav tau electromagnetic induction nyob rau hauv 1831 thiab txij thaum ntawd los nws twb tsis yooj yim sua xav txog tej yam peb lub neej tsis muaj nws.

Faraday pom qhov tshwm sim ntawm cov hluav taws xob tam sim no hauv lub voj kaw vim qhov hloov pauv ntawm cov hlau nplaum sib nqus hla dhau lub voj no. Ib qho kev paub hauv tsev kawm yog paub thaum lub tiaj tus hlau nplaum txav mus rau hauv lub voj voog-zoo li lub voj voog ntawm cov hlau (solenoid), thiab cov hluav taws xob tam sim no tshwm hauv nws. Kuj tseem muaj cov txheej txheem thim rov qab - qhov hloov hluav taws xob tam sim no hauv lub solenoid (coil) tsim ib qho chaw sib nqus sib nqus.

Niaj hnub nimno induction cooker ua haujlwm ntawm tib txoj cai. Nyob rau hauv lub iav-ceramic cua sov vaj huam sib luag (nruab nrab rau electromagnetic oscillations) ntawm xws li ib tug lub qhov cub muaj ib tug induction kauj los ntawm uas cov hluav taws xob tam sim no ntws nrog ib zaus ntawm 20-60 kHz, tsim ib tug alternating magnetic teb uas induces eddy tam sim no nyob rau hauv ib tug nyias txheej. (daim tawv nqaij txheej) ntawm qab ntawm ib lub tais hlau.

Cov hluav taws xob tiv thaiv heats li cov tais diav. Cov dej ntws no tsis muaj kev phom sij ntau dua li cov tais kub kub ntawm cov qhov cub zoo tib yam. Cookware yuav tsum yog hlau los yog cam khwb cia hlau nrog ferromagnetic zog (nrhiav ib tug hlau nplaum).

Lub teeb refraction
Lub teeb refraction

10. Refraction ntawm lub teeb

Lub kaum sab xis ntawm qhov tshwm sim ntawm lub teeb yog sib npaug rau lub kaum sab xis ntawm kev xav, thiab kev nthuav tawm ntawm lub teeb ci los yog lub teeb los ntawm cov teeb pom kev yog piav qhia los ntawm ob, nthwv dej-particle xwm: ntawm ib sab, cov no yog electromagnetic tsis, thiab ntawm qhov tod tes, particles-photons, uas txav ntawm qhov siab tshaj plaws ua tau hauv lub Ntiaj Teb.

Hauv chav ua noj, koj tuaj yeem pom qhov tshwm sim ntawm qhov muag pom zoo li qhov pom ntawm lub teeb. Piv txwv li, thaum muaj lub vase pob tshab nrog cov paj ntawm lub rooj noj mov, cov stems hauv dej zoo li hloov ntawm tus ciam ntawm cov dej saum npoo av txheeb ze rau lawv txuas ntxiv sab nraum cov kua. Qhov tseeb yog tias dej, zoo li lub lens, refracs cov rays ntawm lub teeb reflected los ntawm stems nyob rau hauv lub vase.

Ib qho zoo sib xws yog pom nyob rau hauv lub khob pob tshab tshuaj yej, nyob rau hauv uas ib diav yog dipped. Koj tuaj yeem pom cov duab sib txawv thiab loj ntawm taum lossis cereals hauv qab ntawm lub lauj kaub tob ntawm cov dej ntshiab.

Pom zoo: