{"id":221,"date":"2020-02-21T15:20:55","date_gmt":"2020-02-21T14:20:55","guid":{"rendered":"https:\/\/www.liceoalessandrovolta.edu.it\/measurement\/?page_id=221"},"modified":"2020-02-21T15:23:56","modified_gmt":"2020-02-21T14:23:56","slug":"elettrometro-di-exner","status":"publish","type":"page","link":"https:\/\/www.liceoalessandrovolta.edu.it\/measurement\/elettrometro-di-exner\/","title":{"rendered":"18. Elettrometro di Exner"},"content":{"rendered":"\n<figure class=\"wp-block-image\"><img loading=\"lazy\" decoding=\"async\" width=\"256\" height=\"300\" src=\"https:\/\/www.liceoalessandrovolta.edu.it\/measurement\/wp-content\/uploads\/2020\/02\/20191028_114838-256x300.jpg\" alt=\"\" class=\"wp-image-222\" srcset=\"https:\/\/www.liceoalessandrovolta.edu.it\/measurement\/wp-content\/uploads\/2020\/02\/20191028_114838-256x300.jpg 256w, https:\/\/www.liceoalessandrovolta.edu.it\/measurement\/wp-content\/uploads\/2020\/02\/20191028_114838-768x900.jpg 768w, https:\/\/www.liceoalessandrovolta.edu.it\/measurement\/wp-content\/uploads\/2020\/02\/20191028_114838-874x1024.jpg 874w\" sizes=\"(max-width: 256px) 100vw, 256px\" \/><\/figure>\n\n\n\n<p><strong>IT <\/strong>&#8211; L&#8217;elettrometro, proposto nel 1887 dal fisico tedesco Franz Exner, permette di misurare la differenza di potenziale che si genera tra il pomello superiore (su cui si pone un corpo carico) e l\u2019involucro dell\u2019elettrometro stesso, collegato a terra. Esso \u00e8 composto da una scatola metallica cilindrica, con due aperture circolari in vetro. Possiede due foglie di alluminio la cui divergenza rispetto alla lamina metallica fissa centrale si legge su una scala graduata e permette di ricavare la misura cercata: l&#8217;<a href=\"http:\/\/www.sapere.it\/enciclopedia\/deviazi%C3%B3ne.html\">angolo di deviazione<\/a>, per valori piccoli, \u00e8 infatti proporzionale al quadrato della differenza di potenziale. Ai lati della lamina fissa e\u00a0parallelamente ad essa vi sono infine due piastre metalliche,\u00a0avvicinabili mediante due guide: esse hanno il duplice scopo\u00a0di bloccare le foglioline quando l\u2019elettrometro\u00a0viene trasportato e scaricarlo velocemente durante il funzionamento. <\/p>\n\n\n\n<p><strong>GB<\/strong> &#8211;<strong> \u00a0 <\/strong>Exner\u00a0 electrometer &#8211; The electrometer, proposed in 1887 by the German physicist Franz Exner, allows you to measure the potential difference that is generated between the upper knob (on which a charged body is placed) and the electrometer itself, connected to earth. It is composed of a cylindrical metal box, with two circular glass openings. It has two aluminum leaves whose divergence from the central fixed metal sheet can be read on a graduated scale and allows to obtain the desired measure: the deviation angle, for small values, is in fact proportional to the square of the potential difference. At the sides of the fixed foil and parallel to it there are finally two metal plates, which can be approached by means of two guides: they have the dual purpose of blocking the leaves when the electrometer is transported and discharging it quickly during operation.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>IT &#8211; L&#8217;elettrometro, proposto nel 1887 dal fisico tedesco Franz Exner, permette di misurare la differenza di potenziale che si genera tra il pomello superiore (su cui si pone un&hellip;<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"_links":{"self":[{"href":"https:\/\/www.liceoalessandrovolta.edu.it\/measurement\/wp-json\/wp\/v2\/pages\/221"}],"collection":[{"href":"https:\/\/www.liceoalessandrovolta.edu.it\/measurement\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/www.liceoalessandrovolta.edu.it\/measurement\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/www.liceoalessandrovolta.edu.it\/measurement\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.liceoalessandrovolta.edu.it\/measurement\/wp-json\/wp\/v2\/comments?post=221"}],"version-history":[{"count":4,"href":"https:\/\/www.liceoalessandrovolta.edu.it\/measurement\/wp-json\/wp\/v2\/pages\/221\/revisions"}],"predecessor-version":[{"id":228,"href":"https:\/\/www.liceoalessandrovolta.edu.it\/measurement\/wp-json\/wp\/v2\/pages\/221\/revisions\/228"}],"wp:attachment":[{"href":"https:\/\/www.liceoalessandrovolta.edu.it\/measurement\/wp-json\/wp\/v2\/media?parent=221"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}