{"id":1590,"date":"2026-09-08T08:07:33","date_gmt":"2026-09-08T08:07:33","guid":{"rendered":"https:\/\/maroczain.com\/scolaire.maroczain.com\/?page_id=1590"},"modified":"2026-09-08T08:07:33","modified_gmt":"2026-09-08T08:07:33","slug":"electrostatique-cpge","status":"publish","type":"page","link":"https:\/\/maroczain.com\/scolaire.maroczain.com\/electrostatique-cpge\/","title":{"rendered":"\u00c9lectrostatique CPGE."},"content":{"rendered":"\n&#8220;`html\n<div id=\"mza-electrostatique-cpge\">\n\n<style>\n#mza-electrostatique-cpge,#mza-electrostatique-cpge *{box-sizing:border-box}\n#mza-electrostatique-cpge{\n --navy:#06172c;--navy2:#0d416d;--gold:#c99a36;--gold2:#efd68c;\n --paper:#f5f6f8;--white:#fff;--text:#18283a;--muted:#687789;--line:#dfe5eb;\n font-family:Arial,Helvetica,sans-serif;background:var(--paper);color:var(--text);overflow:hidden\n}\n#mza-electrostatique-cpge a{text-decoration:none;color:inherit}\n#mza-electrostatique-cpge .wrap{max-width:1200px;margin:auto;padding:0 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0;background:#f7f8fa;border-radius:14px\n}\n#mza-electrostatique-cpge .question strong{display:block;color:var(--navy);margin-bottom:12px}\n#mza-electrostatique-cpge label{display:block;padding:8px 0;color:#526174;cursor:pointer}\n#mza-electrostatique-cpge #elecResult{\n display:none;margin-top:18px;padding:20px;border-radius:14px;background:var(--navy);color:#fff\n}\n#mza-electrostatique-cpge .cta{\n text-align:center;padding:50px 24px;border-radius:25px;\n background:linear-gradient(135deg,#06172c,#0d416d);color:#fff\n}\n#mza-electrostatique-cpge .cta h2{color:#fff}\n#mza-electrostatique-cpge .cta p{max-width:760px;margin:0 auto 22px;color:#cfdae4;line-height:1.7}\n\n@media(max-width:900px){\n #mza-electrostatique-cpge .grid,\n #mza-electrostatique-cpge .grid3,\n #mza-electrostatique-cpge .method{grid-template-columns:1fr}\n}\n<\/style>\n\n<header class=\"hero\">\n<div class=\"wrap\">\n\n<span class=\"badge\">COURS 07 \u2022 PHYSIQUE CPGE<\/span>\n\n<h1>Charger.<br>Cr\u00e9er. Potentiels.<\/h1>\n\n<p class=\"lead\">\nL&#8217;\u00e9lectrostatique \u00e9tudie les charges au repos et les champs qu&#8217;elles cr\u00e9ent.\nLa ma\u00eetrise de la loi de Coulomb, du champ \u00e9lectrique, du potentiel,\nde l&#8217;\u00e9nergie et du th\u00e9or\u00e8me de Gauss permet de r\u00e9soudre rapidement\nles distributions poss\u00e9dant de fortes sym\u00e9tries.\n<\/p>\n\n<div class=\"actions\">\n<a href=\"#cours\" class=\"btn gold\">\ud83d\udcda COMMENCER<\/a>\n<a href=\"#methode\" class=\"btn glass\">\ud83e\udde0 M\u00c9THODE<\/a>\n<a href=\"#exercices\" class=\"btn glass\">\ud83e\udde9 EXERCICES<\/a>\n<a href=\"#qcm\" class=\"btn glass\">\u2753 QCM<\/a>\n<\/div>\n\n<\/div>\n<\/header>\n\n<section id=\"cours\">\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">1. CHARGE \u00c9LECTRIQUE<\/span>\n<h2>La source de l&#8217;interaction \u00e9lectrostatique.<\/h2>\n<\/div>\n\n<div class=\"grid\">\n\n<div class=\"card\">\n<h3>Deux signes<\/h3>\n<p>\nLes charges \u00e9lectriques peuvent \u00eatre positives ou n\u00e9gatives.\n<\/p>\n<\/div>\n\n<div class=\"card\">\n<h3>Quantification<\/h3>\n<div class=\"formula\">\nq = n e\n<\/div>\n<p>\navec e la charge \u00e9l\u00e9mentaire.\n<\/p>\n<\/div>\n\n<div class=\"card\">\n<h3>Conservation<\/h3>\n<p>\nDans un syst\u00e8me isol\u00e9, la charge \u00e9lectrique totale se conserve.\n<\/p>\n<\/div>\n\n<div class=\"card\">\n<h3>Unit\u00e9 SI<\/h3>\n<div class=\"formula\">\n[q] = coulomb (C)\n<\/div>\n<\/div>\n\n<\/div>\n<\/div>\n<\/section>\n\n<section style=\"background:#efede7\">\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">2. LOI DE COULOMB<\/span>\n<h2>L&#8217;interaction entre deux charges ponctuelles.<\/h2>\n<\/div>\n\n<div class=\"card\">\n\n<p>\nDeux charges q\u2081 et q\u2082 s\u00e9par\u00e9es par une distance r exercent l&#8217;une sur l&#8217;autre une force :\n<\/p>\n\n<div class=\"formula\">\nF = (1 \/ 4\u03c0\u03b5\u2080) \u00b7 |q\u2081q\u2082| \/ r\u00b2\n<\/div>\n\n<p>\nVectoriellement :\n<\/p>\n\n<div class=\"formula\">\nF<sub>1\u21922<\/sub> =\n(1 \/ 4\u03c0\u03b5\u2080) \u00b7 q\u2081q\u2082 \/ r\u00b2 \u00b7 u<sub>1\u21922<\/sub>\n<\/div>\n\n<div class=\"tip\">\nM\u00eame signe : r\u00e9pulsion. Signes oppos\u00e9s : attraction.\n<\/div>\n\n<\/div>\n<\/section>\n\n<section>\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">3. PRINCIPE DE SUPERPOSITION<\/span>\n<h2>Les champs s&#8217;additionnent vectoriellement.<\/h2>\n<\/div>\n\n<div class=\"card\">\n\n<p>\nSi plusieurs charges produisent un champ en un point M :\n<\/p>\n\n<div class=\"formula\">\nE(M) = \u03a3 E\u1d62(M)\n<\/div>\n\n<p>\nLe principe de superposition est fondamental pour les distributions discr\u00e8tes ou continues.\n<\/p>\n\n<\/div>\n<\/section>\n\n<section style=\"background:#efede7\">\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">4. CHAMP \u00c9LECTRIQUE<\/span>\n<h2>D\u00e9crire l&#8217;action \u00e9lectrique dans l&#8217;espace.<\/h2>\n<\/div>\n\n<div class=\"grid\">\n\n<div class=\"card\">\n<h3>D\u00e9finition<\/h3>\n\n<div class=\"formula\">\nE = F\/q\n<\/div>\n<\/div>\n\n<div class=\"card\">\n<h3>Charge ponctuelle<\/h3>\n\n<div class=\"formula\">\nE =\n(1 \/ 4\u03c0\u03b5\u2080) \u00b7 q\/r\u00b2 \u00b7 u<sub>r<\/sub>\n<\/div>\n<\/div>\n\n<div class=\"card\">\n<h3>Unit\u00e9<\/h3>\n\n<div class=\"formula\">\nV\u00b7m\u207b\u00b9\n<\/div>\n\n<p>ou N\u00b7C\u207b\u00b9.<\/p>\n<\/div>\n\n<div class=\"card\">\n<h3>Force sur une charge<\/h3>\n\n<div class=\"formula\">\nF = qE\n<\/div>\n<\/div>\n\n<\/div>\n<\/div>\n<\/section>\n\n<section id=\"methode\" class=\"dark\">\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\" style=\"color:#efd68c\">MZA ELECTROSTATIC ENGINE<\/span>\n<h2>La m\u00e9thode avant l&#8217;int\u00e9gration.<\/h2>\n<\/div>\n\n<div class=\"method\">\n<div><b>01<\/b><span>DISTRIBUTION<\/span><\/div>\n<div><b>02<\/b><span>SYM\u00c9TRIES<\/span><\/div>\n<div><b>03<\/b><span>DIRECTION<\/span><\/div>\n<div><b>04<\/b><span>SUPERPOSITION<\/span><\/div>\n<div><b>05<\/b><span>INT\u00c9GRER \/ GAUSS<\/span><\/div>\n<div><b>06<\/b><span>CONTR\u00d4LER<\/span><\/div>\n<\/div>\n\n<\/div>\n<\/section>\n\n<section>\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">5. LIGNES DE CHAMP<\/span>\n<h2>Visualiser la g\u00e9om\u00e9trie du champ.<\/h2>\n<\/div>\n\n<div class=\"grid\">\n\n<div class=\"card\">\n<h3>Tangence<\/h3>\n<p>\nLe vecteur champ est tangent aux lignes de champ en chaque point.\n<\/p>\n<\/div>\n\n<div class=\"card\">\n<h3>Sens<\/h3>\n<p>\nLes lignes vont conventionnellement des charges positives vers les charges n\u00e9gatives.\n<\/p>\n<\/div>\n\n<div class=\"card\">\n<h3>Densit\u00e9<\/h3>\n<p>\nUne forte densit\u00e9 de lignes traduit qualitativement un champ plus intense.\n<\/p>\n<\/div>\n\n<div class=\"card\">\n<h3>Pas de croisement<\/h3>\n<p>\nDeux lignes de champ ne peuvent pas se croiser en un point o\u00f9 le champ est d\u00e9fini.\n<\/p>\n<\/div>\n\n<\/div>\n<\/div>\n<\/section>\n\n<section style=\"background:#efede7\">\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">6. POTENTIEL \u00c9LECTROSTATIQUE<\/span>\n<h2>Passer d&#8217;un vecteur \u00e0 un scalaire.<\/h2>\n<\/div>\n\n<div class=\"card\">\n\n<p>\nLe champ \u00e9lectrostatique d\u00e9rive d&#8217;un potentiel V :\n<\/p>\n\n<div class=\"formula\">\nE = -grad V\n<\/div>\n\n<p>\nEn une dimension :\n<\/p>\n\n<div class=\"formula\">\nE<sub>x<\/sub> = -dV\/dx\n<\/div>\n\n<p>\nPour une charge ponctuelle :\n<\/p>\n\n<div class=\"formula\">\nV(r) =\n(1 \/ 4\u03c0\u03b5\u2080) \u00b7 q\/r\n<\/div>\n\n<\/div>\n<\/section>\n\n<section>\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">7. DIFF\u00c9RENCE DE POTENTIEL<\/span>\n<h2>Relier champ et travail.<\/h2>\n<\/div>\n\n<div class=\"card\">\n\n<div class=\"formula\">\nV(B)-V(A) = -\u222b<sub>A<\/sub><sup>B<\/sup> E \u00b7 dl\n<\/div>\n\n<p>\nLe travail de la force \u00e9lectrique sur une charge q vaut :\n<\/p>\n\n<div class=\"formula\">\nW<sub>A\u2192B<\/sub> = q[V(A)-V(B)]\n<\/div>\n\n<\/div>\n<\/section>\n\n<section style=\"background:#efede7\">\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">8. \u00c9NERGIE POTENTIELLE \u00c9LECTRIQUE<\/span>\n<h2>Une charge dans un potentiel.<\/h2>\n<\/div>\n\n<div class=\"card\">\n\n<div class=\"formula\">\nE<sub>p<\/sub> = qV\n<\/div>\n\n<p>\nPour deux charges ponctuelles :\n<\/p>\n\n<div class=\"formula\">\nE<sub>p<\/sub> =\n(1 \/ 4\u03c0\u03b5\u2080) \u00b7 q\u2081q\u2082 \/ r\n<\/div>\n\n<div class=\"tip\">\nLe signe de l&#8217;\u00e9nergie potentielle d\u00e9pend du produit q\u2081q\u2082.\n<\/div>\n\n<\/div>\n<\/section>\n\n<section>\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">9. \u00c9QUIPOTENTIELLES<\/span>\n<h2>Sur une \u00e9quipotentielle, V est constant.<\/h2>\n<\/div>\n\n<div class=\"grid\">\n\n<div class=\"card\">\n<h3>Propri\u00e9t\u00e9<\/h3>\n<p>\nLe champ \u00e9lectrique est perpendiculaire aux surfaces \u00e9quipotentielles.\n<\/p>\n<\/div>\n\n<div class=\"card\">\n<h3>Travail<\/h3>\n<p>\nLe d\u00e9placement d&#8217;une charge le long d&#8217;une \u00e9quipotentielle ne produit pas de travail \u00e9lectrostatique.\n<\/p>\n<\/div>\n\n<\/div>\n<\/div>\n<\/section>\n\n<section style=\"background:#efede7\">\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">10. FLUX DU CHAMP<\/span>\n<h2>Mesurer ce qui traverse une surface.<\/h2>\n<\/div>\n\n<div class=\"card\">\n\n<p>\nLe flux \u00e9l\u00e9mentaire vaut :\n<\/p>\n\n<div class=\"formula\">\nd\u03a6 = E \u00b7 dS\n<\/div>\n\n<p>\nSur une surface S :\n<\/p>\n\n<div class=\"formula\">\n\u03a6 = \u222c<sub>S<\/sub> E \u00b7 dS\n<\/div>\n\n<\/div>\n<\/section>\n\n<section>\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">11. TH\u00c9OR\u00c8ME DE GAUSS<\/span>\n<h2>La puissance des sym\u00e9tries.<\/h2>\n<\/div>\n\n<div class=\"card\">\n\n<p>\nPour toute surface ferm\u00e9e :\n<\/p>\n\n<div class=\"formula\">\n\u222f E \u00b7 dS = Q<sub>int<\/sub>\/\u03b5\u2080\n<\/div>\n\n<p>\nLe th\u00e9or\u00e8me devient particuli\u00e8rement efficace lorsque la distribution poss\u00e8de une sym\u00e9trie sph\u00e9rique, cylindrique ou plane.\n<\/p>\n\n<\/div>\n<\/section>\n\n<section style=\"background:#efede7\">\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">12. STRAT\u00c9GIE DE GAUSS<\/span>\n<h2>Choisir la surface avant de calculer.<\/h2>\n<\/div>\n\n<div class=\"grid3\">\n\n<div class=\"card\">\n<h3>Sym\u00e9trie sph\u00e9rique<\/h3>\n<p>\nSurface de Gauss : sph\u00e8re centr\u00e9e sur la distribution.\n<\/p>\n<\/div>\n\n<div class=\"card\">\n<h3>Sym\u00e9trie cylindrique<\/h3>\n<p>\nSurface de Gauss : cylindre coaxial.\n<\/p>\n<\/div>\n\n<div class=\"card\">\n<h3>Sym\u00e9trie plane<\/h3>\n<p>\nSurface de Gauss : bo\u00eete cylindrique traversant le plan.\n<\/p>\n<\/div>\n\n<\/div>\n<\/div>\n<\/section>\n\n<section>\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">13. EXEMPLE \u2014 CHARGE SPH\u00c9RIQUE<\/span>\n<h2>\u00c0 l&#8217;ext\u00e9rieur, la distribution se comporte comme une charge ponctuelle.<\/h2>\n<\/div>\n\n<div class=\"card\">\n\n<p>\nPour une distribution sph\u00e9rique de charge totale Q et pour r ext\u00e9rieur :\n<\/p>\n\n<div class=\"formula\">\nE(r) =\n(1 \/ 4\u03c0\u03b5\u2080) \u00b7 Q\/r\u00b2 \u00b7 u<sub>r<\/sub>\n<\/div>\n\n<p>\nCe r\u00e9sultat provient directement du th\u00e9or\u00e8me de Gauss.\n<\/p>\n\n<\/div>\n<\/section>\n\n<section style=\"background:#efede7\">\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">14. PLAN INFINI CHARG\u00c9<\/span>\n<h2>Champ uniforme de part et d&#8217;autre.<\/h2>\n<\/div>\n\n<div class=\"card\">\n\n<p>\nPour un plan infini portant une densit\u00e9 surfacique uniforme \u03c3 :\n<\/p>\n\n<div class=\"formula\">\nE = \u03c3 \/ (2\u03b5\u2080)\n<\/div>\n\n<p>\nLe champ est normal au plan.\n<\/p>\n\n<\/div>\n<\/section>\n\n<section>\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">15. CONDUCTEUR \u00c0 L&#8217;\u00c9QUILIBRE \u00c9LECTROSTATIQUE<\/span>\n<h2>Les charges libres se r\u00e9organisent.<\/h2>\n<\/div>\n\n<div class=\"grid\">\n\n<div class=\"card\">\n<h3>Champ int\u00e9rieur<\/h3>\n<div class=\"formula\">\nE = 0\n<\/div>\n<p>dans le mat\u00e9riau conducteur \u00e0 l&#8217;\u00e9quilibre.<\/p>\n<\/div>\n\n<div class=\"card\">\n<h3>Potentiel<\/h3>\n<p>\nLe conducteur est \u00e9quipotentiel.\n<\/p>\n<\/div>\n\n<div class=\"card\">\n<h3>Charges<\/h3>\n<p>\nL&#8217;exc\u00e8s de charge se place sur la surface du conducteur.\n<\/p>\n<\/div>\n\n<div class=\"card\">\n<h3>Champ \u00e0 la surface<\/h3>\n<p>\nLe champ est normal \u00e0 la surface en l&#8217;absence de courant.\n<\/p>\n<\/div>\n\n<\/div>\n<\/div>\n<\/section>\n\n<section style=\"background:#efede7\">\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">16. CONDENSATEUR PLAN<\/span>\n<h2>Cr\u00e9er presque un champ uniforme.<\/h2>\n<\/div>\n\n<div class=\"card\">\n\n<p>\nEntre deux grandes armatures planes oppos\u00e9ment charg\u00e9es :\n<\/p>\n\n<div class=\"formula\">\nE \u2248 \u03c3\/\u03b5\u2080\n<\/div>\n\n<p>\nSi la distance entre les plaques est d :\n<\/p>\n\n<div class=\"formula\">\nU = Ed\n<\/div>\n\n<p>\nLa capacit\u00e9 du condensateur plan id\u00e9al vaut :\n<\/p>\n\n<div class=\"formula\">\nC = \u03b5\u2080S\/d\n<\/div>\n\n<\/div>\n<\/section>\n\n<section id=\"exercices\">\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">17. EXERCICES PROGRESSIFS<\/span>\n<h2>Sym\u00e9trie avant int\u00e9gration.<\/h2>\n<\/div>\n\n<div class=\"exercise\">\n<span class=\"level\">NIVEAU 1<\/span>\n<h3>Exercice 1 \u2014 Deux charges<\/h3>\n<p>\nDeux charges identiques +q sont plac\u00e9es sym\u00e9triquement de part et d&#8217;autre de l&#8217;origine.\nD\u00e9terminer la direction du champ au milieu.\n<\/p>\n<button type=\"button\" class=\"btn gold\" onclick=\"mzaElecHint('eHint1')\">\ud83d\udca1 INDICE<\/button>\n<div id=\"eHint1\" class=\"hint\">\nUtilisez la sym\u00e9trie avant tout calcul num\u00e9rique.\n<\/div>\n<\/div>\n\n<div class=\"exercise\">\n<span class=\"level\">NIVEAU 2<\/span>\n<h3>Exercice 2 \u2014 Potentiel de deux charges<\/h3>\n<p>\nDeux charges q\u2081 et q\u2082 sont plac\u00e9es en A et B.\n\u00c9crire le potentiel en un point M.\n<\/p>\n<button type=\"button\" class=\"btn gold\" onclick=\"mzaElecHint('eHint2')\">\ud83d\udca1 INDICE<\/button>\n<div id=\"eHint2\" class=\"hint\">\nLe potentiel est une grandeur scalaire : additionnez directement les contributions.\n<\/div>\n<\/div>\n\n<div class=\"exercise\">\n<span class=\"level\">NIVEAU 3<\/span>\n<h3>Exercice 3 \u2014 Fil infini<\/h3>\n<p>\nUn fil infini porte une densit\u00e9 lin\u00e9ique uniforme \u03bb.\nD\u00e9terminer la d\u00e9pendance du champ avec la distance r au fil.\n<\/p>\n<button type=\"button\" class=\"btn gold\" onclick=\"mzaElecHint('eHint3')\">\ud83d\udca1 INDICE<\/button>\n<div id=\"eHint3\" class=\"hint\">\nUtilisez une surface de Gauss cylindrique coaxiale au fil.\n<\/div>\n<\/div>\n\n<div class=\"exercise\">\n<span class=\"level\">NIVEAU PR\u00c9PA<\/span>\n<h3>Exercice 4 \u2014 Sph\u00e8re uniform\u00e9ment charg\u00e9e<\/h3>\n<p>\nUne sph\u00e8re pleine de rayon R porte une densit\u00e9 volumique uniforme \u03c1.\nD\u00e9terminer E(r) pour r&lt;R puis pour r&gt;R.\n<\/p>\n<button type=\"button\" class=\"btn gold\" onclick=\"mzaElecHint('eHint4')\">\ud83d\udca1 INDICE<\/button>\n<div id=\"eHint4\" class=\"hint\">\nPour r&lt;R, seule la charge contenue dans la sph\u00e8re de rayon r intervient dans Gauss.\n<\/div>\n<\/div>\n\n<\/div>\n<\/section>\n\n<section style=\"background:#efede7\">\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">18. PROBLEM LAB<\/span>\n<h2>Mission : condensateur plan et particule charg\u00e9e.<\/h2>\n<\/div>\n\n<div class=\"card\">\n\n<h3>Situation<\/h3>\n\n<p>\nDeux plaques parall\u00e8les s\u00e9par\u00e9es d&#8217;une distance d sont soumises \u00e0 une diff\u00e9rence de potentiel U.\nUne particule de masse m et de charge q entre entre les plaques avec une vitesse initiale horizontale v\u2080.\n<\/p>\n\n<p>Votre mission :<\/p>\n\n<ol>\n<li>d\u00e9terminer le champ \u00e9lectrique entre les plaques ;<\/li>\n<li>pr\u00e9ciser sa direction et son sens ;<\/li>\n<li>\u00e9crire la force \u00e9lectrique sur la particule ;<\/li>\n<li>d\u00e9terminer son acc\u00e9l\u00e9ration ;<\/li>\n<li>\u00e9tablir les \u00e9quations horaires x(t) et y(t) ;<\/li>\n<li>\u00e9liminer t pour obtenir la trajectoire ;<\/li>\n<li>identifier les param\u00e8tres contr\u00f4lant la d\u00e9viation ;<\/li>\n<li>\u00e9tudier l&#8217;effet du signe de q ;<\/li>\n<li>v\u00e9rifier l&#8217;homog\u00e9n\u00e9it\u00e9 du r\u00e9sultat final.<\/li>\n<\/ol>\n\n<div class=\"actions\">\n<button type=\"button\" class=\"btn gold\" onclick=\"mzaElecHint('eMission1')\">\ud83d\udca1 INDICE<\/button>\n<button type=\"button\" class=\"btn\" style=\"background:#06172c;color:#fff\" onclick=\"mzaElecHint('eMission2')\">\ud83e\udde0 M\u00c9THODE<\/button>\n<\/div>\n\n<div id=\"eMission1\" class=\"hint\">\nDans le mod\u00e8le id\u00e9al du condensateur plan, E = U\/d et le champ est suppos\u00e9 uniforme entre les plaques.\n<\/div>\n\n<div id=\"eMission2\" class=\"hint\">\nLe mouvement horizontal peut rester uniforme tandis que le mouvement transverse devient uniform\u00e9ment acc\u00e9l\u00e9r\u00e9. Traitez s\u00e9par\u00e9ment les deux directions avant d&#8217;\u00e9liminer le temps.\n<\/div>\n\n<\/div>\n<\/div>\n<\/section>\n\n<section class=\"dark\">\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\" style=\"color:#efd68c\">MZA GAUSS CHECK<\/span>\n<h2>Les six r\u00e9flexes \u00e9lectrostatiques.<\/h2>\n<\/div>\n\n<div class=\"method\">\n<div><b>A<\/b><span>CHARGES<\/span><\/div>\n<div><b>B<\/b><span>SYM\u00c9TRIES<\/span><\/div>\n<div><b>C<\/b><span>DIRECTION<\/span><\/div>\n<div><b>D<\/b><span>SURFACE<\/span><\/div>\n<div><b>E<\/b><span>FLUX<\/span><\/div>\n<div><b>F<\/b><span>LIMITES<\/span><\/div>\n<\/div>\n\n<\/div>\n<\/section>\n\n<section id=\"qcm\">\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">19. QCM DE VALIDATION<\/span>\n<h2>Diagnostic \u00c9lectrostatique CPGE.<\/h2>\n<p>Le score est affich\u00e9 sans r\u00e9v\u00e9ler les r\u00e9ponses correctes.<\/p>\n<\/div>\n\n<div class=\"qcm\">\n\n<form id=\"elecQuiz\">\n\n<div class=\"question\">\n<strong>1. Le champ cr\u00e9\u00e9 par une charge ponctuelle d\u00e9cro\u00eet comme :<\/strong>\n<label><input type=\"radio\" name=\"el1\" value=\"1\"> 1\/r\u00b2<\/label>\n<label><input type=\"radio\" name=\"el1\" value=\"0\"> r\u00b2<\/label>\n<label><input type=\"radio\" name=\"el1\" value=\"0\"> 1\/r<\/label>\n<label><input type=\"radio\" name=\"el1\" value=\"0\"> r<\/label>\n<\/div>\n\n<div class=\"question\">\n<strong>2. La force sur une charge q plac\u00e9e dans un champ E vaut :<\/strong>\n<label><input type=\"radio\" name=\"el2\" value=\"1\"> F=qE<\/label>\n<label><input type=\"radio\" name=\"el2\" value=\"0\"> F=E\/q<\/label>\n<label><input type=\"radio\" name=\"el2\" value=\"0\"> F=q\/E<\/label>\n<label><input type=\"radio\" name=\"el2\" value=\"0\"> F=q+E<\/label>\n<\/div>\n\n<div class=\"question\">\n<strong>3. Le champ \u00e9lectrostatique est reli\u00e9 au potentiel par :<\/strong>\n<label><input type=\"radio\" name=\"el3\" value=\"1\"> E=-grad V<\/label>\n<label><input type=\"radio\" name=\"el3\" value=\"0\"> E=V\u00b2<\/label>\n<label><input type=\"radio\" name=\"el3\" value=\"0\"> E=qV<\/label>\n<label><input type=\"radio\" name=\"el3\" value=\"0\"> E=grad V sans signe moins<\/label>\n<\/div>\n\n<div class=\"question\">\n<strong>4. Le th\u00e9or\u00e8me de Gauss relie le flux du champ \u00e0 :<\/strong>\n<label><input type=\"radio\" name=\"el4\" value=\"1\"> la charge int\u00e9rieure<\/label>\n<label><input type=\"radio\" name=\"el4\" value=\"0\"> la masse totale<\/label>\n<label><input type=\"radio\" name=\"el4\" value=\"0\"> la vitesse des charges<\/label>\n<label><input type=\"radio\" name=\"el4\" value=\"0\"> l&#8217;\u00e9nergie cin\u00e9tique<\/label>\n<\/div>\n\n<div class=\"question\">\n<strong>5. \u00c0 l&#8217;\u00e9quilibre \u00e9lectrostatique, dans le mat\u00e9riau d&#8217;un conducteur :<\/strong>\n<label><input type=\"radio\" name=\"el5\" value=\"1\"> E=0<\/label>\n<label><input type=\"radio\" name=\"el5\" value=\"0\"> E est maximal<\/label>\n<label><input type=\"radio\" name=\"el5\" value=\"0\"> V=0 forc\u00e9ment<\/label>\n<label><input type=\"radio\" name=\"el5\" value=\"0\"> les charges circulent en permanence<\/label>\n<\/div>\n\n<div class=\"question\">\n<strong>6. Le champ \u00e9lectrique est :<\/strong>\n<label><input type=\"radio\" name=\"el6\" value=\"1\"> perpendiculaire aux \u00e9quipotentielles<\/label>\n<label><input type=\"radio\" name=\"el6\" value=\"0\"> toujours tangent aux \u00e9quipotentielles<\/label>\n<label><input type=\"radio\" name=\"el6\" value=\"0\"> ind\u00e9pendant du potentiel<\/label>\n<label><input type=\"radio\" name=\"el6\" value=\"0\"> toujours nul sur une \u00e9quipotentielle<\/label>\n<\/div>\n\n<button type=\"button\" class=\"btn gold\" onclick=\"mzaElecScore()\">\nVALIDER MON QCM\n<\/button>\n\n<\/form>\n\n<div id=\"elecResult\"><\/div>\n\n<\/div>\n<\/div>\n<\/section>\n\n<section>\n<div class=\"wrap\">\n\n<div class=\"cta\">\n\n<div style=\"font-size:43px\">\u222f E\u00b7dS = Q\/\u03b5\u2080<\/div>\n\n<h2>En \u00e9lectrostatique, la sym\u00e9trie vaut souvent plus qu&#8217;une longue int\u00e9gration.<\/h2>\n\n<p>\nIdentifier la distribution, rep\u00e9rer les invariances et sym\u00e9tries,\nchoisir la bonne surface de Gauss puis contr\u00f4ler les limites permet\nde traiter efficacement les champs \u00e9lectriques les plus classiques.\n<\/p>\n\n<div class=\"actions\" style=\"justify-content:center\">\n<a href=\"#cours\" class=\"btn gold\">\ud83d\udcda REVOIR LE COURS<\/a>\n<a href=\"#exercices\" class=\"btn glass\">\ud83e\udde9 EXERCICES<\/a>\n<a href=\"#qcm\" class=\"btn glass\">\u2753 REFAIRE LE QCM<\/a>\n<\/div>\n\n<\/div>\n<\/div>\n<\/section>\n\n<script>\nfunction mzaElecHint(id){\n const el=document.getElementById(id);\n if(!el)return;\n el.style.display = el.style.display===\"block\" ? \"none\" : \"block\";\n}\n\nfunction mzaElecScore(){\n const form=document.getElementById(\"elecQuiz\");\n const result=document.getElementById(\"elecResult\");\n\n let score=0;\n let complete=true;\n\n [\"el1\",\"el2\",\"el3\",\"el4\",\"el5\",\"el6\"].forEach(function(name){\n   const answer=form.querySelector('input[name=\"'+name+'\"]:checked');\n   if(!answer){\n     complete=false;\n   }else{\n     score+=Number(answer.value);\n   }\n });\n\n result.style.display=\"block\";\n\n if(!complete){\n   result.innerHTML=\"<strong>R\u00e9pondez aux 6 questions avant de valider.<\/strong>\";\n   return;\n }\n\n const pct=Math.round(score\/6*100);\n\n let level=\"\u00c9lectrostatique \u00e0 consolider\";\n if(pct>=50) level=\"Fondations acquises\";\n if(pct>=67) level=\"Bon niveau\";\n if(pct>=84) level=\"Tr\u00e8s bonne ma\u00eetrise\";\n if(pct===100) level=\"Excellent niveau CPGE\";\n\n result.innerHTML=\n \"<strong style='font-size:30px;color:#efd68c'>\"+pct+\"%<\/strong>\"+\n \"<p><b>\"+level+\"<\/b><\/p>\"+\n \"<p>Score : \"+score+\" \/ 6<\/p>\"+\n \"<p>Les r\u00e9ponses correctes et la correction d\u00e9taill\u00e9e restent masqu\u00e9es.<\/p>\";\n}\n<\/script>\n\n<\/div>\n&#8220;`\n","protected":false},"excerpt":{"rendered":"<p>&#8220;`html COURS 07 \u2022 PHYSIQUE CPGE Charger.Cr\u00e9er. Potentiels. L&#8217;\u00e9lectrostatique \u00e9tudie les charges au repos et les champs qu&#8217;elles cr\u00e9ent. La ma\u00eetrise de la loi de Coulomb, du champ \u00e9lectrique, du potentiel, de l&#8217;\u00e9nergie et du th\u00e9or\u00e8me de Gauss permet de r\u00e9soudre rapidement les distributions poss\u00e9dant de fortes sym\u00e9tries. \ud83d\udcda COMMENCER \ud83e\udde0 M\u00c9THODE \ud83e\udde9 EXERCICES \u2753 [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"","meta":{"footnotes":""},"class_list":["post-1590","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/maroczain.com\/scolaire.maroczain.com\/wp-json\/wp\/v2\/pages\/1590","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/maroczain.com\/scolaire.maroczain.com\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/maroczain.com\/scolaire.maroczain.com\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/maroczain.com\/scolaire.maroczain.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/maroczain.com\/scolaire.maroczain.com\/wp-json\/wp\/v2\/comments?post=1590"}],"version-history":[{"count":1,"href":"https:\/\/maroczain.com\/scolaire.maroczain.com\/wp-json\/wp\/v2\/pages\/1590\/revisions"}],"predecessor-version":[{"id":1592,"href":"https:\/\/maroczain.com\/scolaire.maroczain.com\/wp-json\/wp\/v2\/pages\/1590\/revisions\/1592"}],"wp:attachment":[{"href":"https:\/\/maroczain.com\/scolaire.maroczain.com\/wp-json\/wp\/v2\/media?parent=1590"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}