Resistance gaban zazzabi

Daya daga cikin halaye na wani electrically conductive abu - wannan juriya a kan zazzabi. Idan aka wakilta a matsayin mai jadawali a kan wani daidaita jirgin sama, a cikinsa lokacin jinkiri suna alama a kan kwance axis (t), da kuma a tsaye - tamanin da ohmic juriya (R), to za mu sami karye line. A zafin jiki dogara da juriya schematically kunshi uku sassan. A farko yayi dace a kananan zafi - wannan lokaci da juriya ya canjãwa sosai kadan. Wannan ya faru a wasu batu, bayan da layi a kan jadawali da ke hawa da cika fuska - wannan shi ne karo na biyu da mãkirci. Uku, da karshen bangaren - An mike lullube sama daga cikin aya a da tsaya R tsawo, a wata gwada da kananan kwana da kwance axis.

A zahirin ma'anar wannan jadawali ne da wadannan: juriya da zazzabi dogara da shugaba ne aka bayyana ta a sauki mikakke lissafi muddin dumama yawa ba ya wuce wasu darajar halayyar ga wannan musamman kayan. Ga m misali: idan a + 10 ° C material juriya ne 10 ohms, sa'an nan zuwa 40 ° C darajar R ba zai canza, sauran da iyãkõkin ji kuskure. Amma ko da a 41 ° C Jump a cikin juriya taso to 70 ohms. Idan wani m karuwa a yawan zafin jiki ba za ta daina, don kowace m digiri zai fada wani ƙarin 5 ohms.

Wannan dukiya ne yadu a yi amfani daban-daban lantarki na'urorin, don haka ta halitta haifar da bayanai a kan jan matsayin daya daga cikin na kowa kayan a lantarki da inji. Saboda haka, domin a jan zafi shugaba ga kowane ƙarin digiri karuwa a juriya take kaiwa zuwa rabin kashi na musamman darajar (da za a samu a cikin nusar da alluna, an saita zuwa 20 ° C, 1 m dogon sashe na 1 mm²).

A taron na wani ƙarfe shugaba electromotive karfi EMF bayyana lantarki - directed motsi na na farko barbashi tare da cajin. Ions ba a cikin nodes na da crystalline raga na karfe, ba zai iya rike dogon electrons a cikin matsanancin falakinsu, don haka ba za su iya matsawa da yardar kaina a ko'ina cikin girma da abu daga wani kumburi zuwa wani. Wannan bazuwar motsi sa ta waje makamashi - zafi.

Ko da yake gaskiya na motsi ne ba, shi ba directed, duk da haka ba a matsayin halin yanzu. Lokacin da lantarki filin, da electrons suna daidaitacce daidai da ta sanyi, kafa directed motsi. Amma a matsayin thermal sakamako bai bace, da ka motsi barbashi yi karo da directed filin. A dogara da juriya da karafa da zazzabi nuna adadin kutse zuwa da nassi na yanzu. A mafi girma da yawan zafin jiki, da hakan da R shugaba.

A bayyane ƙarshe: rage mataki na dumama za a iya rage da kuma juriya. Hanyar jejjerawa (game da 20 ° K) kawai halin da wani gagarumin raguwa na thermal m motsi na barbashi cikin abu.

La'akari da kaddarorin na conductive abu ne yadu a yi amfani da lantarki aikin injiniya. Alal misali, dogaro na da shugaba juriya da zazzabi amfani da lantarki masu auna sigina. Sanin darajar da wani abu za a iya kerarre thermistor, gama da shi zuwa dijital ko analog karatu na'urar, yi da ya dace grading sikelin kuma yi amfani da matsayin madadin su da Mercury ma'aunin zafi da sanyio. A zuciya na mafi zamani thermal na'urori masu auna sigina aza daidai wannan manufa, domin mafi girma AMINCI, da kuma sauki zane.

Bugu da ari, zazzabi dogara da juriya dumama sa ya yiwu yin lissafi da mota windings.