{"id":1575,"date":"2026-09-08T08:07:50","date_gmt":"2026-09-08T08:07:50","guid":{"rendered":"https:\/\/maroczain.com\/scolaire.maroczain.com\/?page_id=1575"},"modified":"2026-09-08T08:07:50","modified_gmt":"2026-09-08T08:07:50","slug":"cinematique-du-point-cpge","status":"publish","type":"page","link":"https:\/\/maroczain.com\/scolaire.maroczain.com\/cinematique-du-point-cpge\/","title":{"rendered":"Cin\u00e9matique du point CPGE,"},"content":{"rendered":"\n&#8220;`html\n<div id=\"mza-cinematique-cpge\">\n\n<style>\n#mza-cinematique-cpge,#mza-cinematique-cpge *{box-sizing:border-box}\n#mza-cinematique-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-cinematique-cpge a{text-decoration:none;color:inherit}\n#mza-cinematique-cpge .wrap{max-width:1200px;margin:auto;padding:0 24px}\n#mza-cinematique-cpge section{padding:68px 0}\n#mza-cinematique-cpge .hero{\n color:#fff;padding:72px 0;\n background:\n radial-gradient(circle at 84% 15%,rgba(213,169,68,.28),transparent 28%),\n linear-gradient(135deg,#041224,#082b4c 65%,#10517e)\n}\n#mza-cinematique-cpge .badge{\n display:inline-block;padding:8px 13px;border-radius:999px;\n border:1px solid rgba(239,214,140,.4);color:var(--gold2);\n font-size:11px;font-weight:900;letter-spacing:1.3px\n}\n#mza-cinematique-cpge h1{\n font:500 clamp(42px,7vw,72px)\/1 Georgia,serif;margin:17px 0;color:#fff\n}\n#mza-cinematique-cpge .lead{max-width:900px;color:#d5e1ea;font-size:18px;line-height:1.75}\n#mza-cinematique-cpge .actions{display:flex;gap:9px;flex-wrap:wrap;margin-top:26px}\n#mza-cinematique-cpge .btn{\n min-height:47px;padding:0 18px;border:none;border-radius:10px;\n display:inline-flex;align-items:center;justify-content:center;cursor:pointer;\n font-size:12px;font-weight:900\n}\n#mza-cinematique-cpge 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span{font-size:10px;font-weight:900}\n#mza-cinematique-cpge .exercise{\n background:#fff;border:1px solid var(--line);border-radius:18px;padding:22px;margin-bottom:14px\n}\n#mza-cinematique-cpge .exercise h3{color:var(--navy);margin:0 0 10px}\n#mza-cinematique-cpge .level{\n display:inline-block;padding:6px 9px;margin-bottom:10px;border-radius:999px;\n background:#f1eee5;color:#7b5b1d;font-size:10px;font-weight:900\n}\n#mza-cinematique-cpge .exercise p{color:var(--muted);line-height:1.7}\n#mza-cinematique-cpge .hint{\n display:none;margin-top:12px;padding:15px;border-radius:12px;\n background:#eef3f7;color:#425469;line-height:1.65\n}\n#mza-cinematique-cpge .qcm{\n background:#fff;border:1px solid var(--line);border-radius:23px;padding:28px\n}\n#mza-cinematique-cpge .question{\n padding:20px;margin:15px 0;background:#f7f8fa;border-radius:14px\n}\n#mza-cinematique-cpge .question strong{display:block;color:var(--navy);margin-bottom:12px}\n#mza-cinematique-cpge label{display:block;padding:8px 0;color:#526174;cursor:pointer}\n#mza-cinematique-cpge #cinResult{\n display:none;margin-top:18px;padding:20px;border-radius:14px;background:var(--navy);color:#fff\n}\n#mza-cinematique-cpge .cta{\n text-align:center;padding:50px 24px;border-radius:25px;\n background:linear-gradient(135deg,#06172c,#0d416d);color:#fff\n}\n#mza-cinematique-cpge .cta h2{color:#fff}\n#mza-cinematique-cpge .cta p{max-width:760px;margin:0 auto 22px;color:#cfdae4;line-height:1.7}\n\n@media(max-width:900px){\n #mza-cinematique-cpge .grid,\n #mza-cinematique-cpge .grid3,\n #mza-cinematique-cpge .method{grid-template-columns:1fr}\n}\n<\/style>\n\n<header class=\"hero\">\n<div class=\"wrap\">\n\n<span class=\"badge\">COURS 02 \u2022 PHYSIQUE CPGE<\/span>\n\n<h1>D\u00e9crire.<br>D\u00e9river. Interpr\u00e9ter.<\/h1>\n\n<p class=\"lead\">\nLa cin\u00e9matique d\u00e9crit le mouvement sans chercher encore sa cause.\nPosition, trajectoire, vitesse et acc\u00e9l\u00e9ration constituent le langage\nfondamental de toute la m\u00e9canique.\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. R\u00c9F\u00c9RENTIEL<\/span>\n<h2>Un mouvement n&#8217;existe que relativement \u00e0 un observateur.<\/h2>\n<\/div>\n\n<div class=\"grid\">\n\n<div class=\"card\">\n<h3>R\u00e9f\u00e9rentiel<\/h3>\n<p>\nUn r\u00e9f\u00e9rentiel associe un rep\u00e8re spatial et une mesure du temps.\n<\/p>\n<\/div>\n\n<div class=\"card\">\n<h3>Relativit\u00e9 du mouvement<\/h3>\n<p>\nUn passager assis dans un train est immobile par rapport au train,\nmais en mouvement par rapport au sol.\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\">2. VECTEUR POSITION<\/span>\n<h2>Rep\u00e9rer le point mat\u00e9riel.<\/h2>\n<\/div>\n\n<div class=\"card\">\n\n<p>\nDans un rep\u00e8re cart\u00e9sien :\n<\/p>\n\n<div class=\"formula\">\nOM(t) = x(t)e\u2093 + y(t)e\u1d67 + z(t)e_z\n<\/div>\n\n<p>\nLa connaissance des fonctions x(t), y(t), z(t) permet de reconstruire la trajectoire.\n<\/p>\n\n<\/div>\n<\/div>\n<\/section>\n\n<section>\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">3. VITESSE<\/span>\n<h2>Mesurer la variation de position.<\/h2>\n<\/div>\n\n<div class=\"grid\">\n\n<div class=\"card\">\n<h3>D\u00e9finition vectorielle<\/h3>\n\n<div class=\"formula\">\nv = d(OM)\/dt\n<\/div>\n<\/div>\n\n<div class=\"card\">\n<h3>Coordonn\u00e9es cart\u00e9siennes<\/h3>\n\n<div class=\"formula\">\nv = x'(t)e\u2093 + y'(t)e\u1d67 + z'(t)e_z\n<\/div>\n<\/div>\n\n<div class=\"card\">\n<h3>Norme<\/h3>\n\n<div class=\"formula\">\n||v|| = \u221a(x&#8217;\u00b2+y&#8217;\u00b2+z&#8217;\u00b2)\n<\/div>\n<\/div>\n\n<div class=\"card\">\n<h3>Interpr\u00e9tation<\/h3>\n<p>\nLe vecteur vitesse est tangent \u00e0 la trajectoire et orient\u00e9 dans le sens du mouvement.\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\">4. ACC\u00c9L\u00c9RATION<\/span>\n<h2>Mesurer la variation de vitesse.<\/h2>\n<\/div>\n\n<div class=\"grid\">\n\n<div class=\"card\">\n<h3>D\u00e9finition<\/h3>\n\n<div class=\"formula\">\na = dv\/dt\n<\/div>\n<\/div>\n\n<div class=\"card\">\n<h3>Position<\/h3>\n\n<div class=\"formula\">\na = d\u00b2(OM)\/dt\u00b2\n<\/div>\n<\/div>\n\n<div class=\"card\">\n<h3>Coordonn\u00e9es cart\u00e9siennes<\/h3>\n\n<div class=\"formula\">\na = x&#8221;e\u2093 + y&#8221;e\u1d67 + z&#8221;e_z\n<\/div>\n<\/div>\n\n<div class=\"card\">\n<h3>Attention<\/h3>\n<p>\nUne vitesse constante en norme peut malgr\u00e9 tout correspondre \u00e0 une acc\u00e9l\u00e9ration non nulle si sa direction change.\n<\/p>\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 KINEMATICS ENGINE<\/span>\n<h2>La m\u00e9thode en six \u00e9tapes.<\/h2>\n<\/div>\n\n<div class=\"method\">\n<div><b>01<\/b><span>R\u00c9F\u00c9RENTIEL<\/span><\/div>\n<div><b>02<\/b><span>REP\u00c8RE<\/span><\/div>\n<div><b>03<\/b><span>POSITION<\/span><\/div>\n<div><b>04<\/b><span>D\u00c9RIVER<\/span><\/div>\n<div><b>05<\/b><span>INTERPR\u00c9TER<\/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. MOUVEMENT RECTILIGNE UNIFORME<\/span>\n<h2>Vitesse constante.<\/h2>\n<\/div>\n\n<div class=\"card\">\n\n<div class=\"formula\">\na = 0\n<\/div>\n\n<div class=\"formula\">\nv = constante\n<\/div>\n\n<div class=\"formula\">\nx(t)=x\u2080+vt\n<\/div>\n\n<p>\nLa trajectoire est une droite et le vecteur vitesse ne varie pas.\n<\/p>\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. MOUVEMENT RECTILIGNE UNIFORM\u00c9MENT ACC\u00c9L\u00c9R\u00c9<\/span>\n<h2>Acc\u00e9l\u00e9ration constante.<\/h2>\n<\/div>\n\n<div class=\"card\">\n\n<div class=\"formula\">\na = constante\n<\/div>\n\n<div class=\"formula\">\nv(t)=v\u2080+at\n<\/div>\n\n<div class=\"formula\">\nx(t)=x\u2080+v\u2080t+\u00bdat\u00b2\n<\/div>\n\n<div class=\"formula\">\nv\u00b2-v\u2080\u00b2 = 2a(x-x\u2080)\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\">7. MOUVEMENT CIRCULAIRE<\/span>\n<h2>Changer de direction cr\u00e9e une acc\u00e9l\u00e9ration.<\/h2>\n<\/div>\n\n<div class=\"grid\">\n\n<div class=\"card\">\n<h3>Position<\/h3>\n\n<div class=\"formula\">\nr = R e\u1d63\n<\/div>\n<\/div>\n\n<div class=\"card\">\n<h3>Vitesse<\/h3>\n\n<div class=\"formula\">\nv = R \u03b8\u0307 e\u03b8\n<\/div>\n<\/div>\n\n<div class=\"card\">\n<h3>Acc\u00e9l\u00e9ration<\/h3>\n\n<div class=\"formula\">\na = -R \u03b8\u0307\u00b2 e\u1d63 + R \u03b8\u0308 e\u03b8\n<\/div>\n<\/div>\n\n<div class=\"card\">\n<h3>Mouvement circulaire uniforme<\/h3>\n\n<div class=\"formula\">\n\u03b8\u0307 = \u03c9 = constante\n<\/div>\n\n<div class=\"formula\">\na = -R\u03c9\u00b2 e\u1d63\n<\/div>\n\n<p>\nL&#8217;acc\u00e9l\u00e9ration est centrip\u00e8te.\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\">8. COORDONN\u00c9ES POLAIRES<\/span>\n<h2>Un outil essentiel pour les mouvements plans.<\/h2>\n<\/div>\n\n<div class=\"card\">\n\n<div class=\"formula\">\nOM = r e\u1d63\n<\/div>\n\n<div class=\"formula\">\nv = \u1e59 e\u1d63 + r\u03b8\u0307 e\u03b8\n<\/div>\n\n<div class=\"formula\">\na = (r\u0308-r\u03b8\u0307\u00b2)e\u1d63 + (r\u03b8\u0308+2\u1e59\u03b8\u0307)e\u03b8\n<\/div>\n\n<\/div>\n\n<div class=\"tip\">\nLe terme 2\u1e59\u03b8\u0307 est souvent oubli\u00e9. Il appara\u00eet parce que la base polaire elle-m\u00eame tourne.\n<\/div>\n\n<\/div>\n<\/section>\n\n<section>\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">9. TRAJECTOIRE PARAM\u00c9TRIQUE<\/span>\n<h2>\u00c9liminer le temps.<\/h2>\n<\/div>\n\n<div class=\"card\">\n\n<p>\nSi :\n<\/p>\n\n<div class=\"formula\">\nx = x(t)<br>\ny = y(t)\n<\/div>\n\n<p>\non cherche \u00e0 \u00e9liminer t afin d&#8217;obtenir une relation :\n<\/p>\n\n<div class=\"formula\">\nF(x,y)=0\n<\/div>\n\n<p>\nCette relation d\u00e9crit g\u00e9om\u00e9triquement la trajectoire.\n<\/p>\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. MOUVEMENT PARABOLIQUE<\/span>\n<h2>Un grand classique.<\/h2>\n<\/div>\n\n<div class=\"card\">\n\n<p>\nPour un projectile lanc\u00e9 avec vitesse initiale v\u2080 sous un angle \u03b1,\nen l&#8217;absence de frottement :\n<\/p>\n\n<div class=\"formula\">\nx(t)=v\u2080 cos(\u03b1)t\n<\/div>\n\n<div class=\"formula\">\ny(t)=v\u2080 sin(\u03b1)t &#8211; \u00bdgt\u00b2\n<\/div>\n\n<p>\nEn \u00e9liminant t :\n<\/p>\n\n<div class=\"formula\">\ny = x tan(\u03b1) &#8211; g x\u00b2 \/ [2v\u2080\u00b2 cos\u00b2(\u03b1)]\n<\/div>\n\n<p>\nLa trajectoire est une parabole.\n<\/p>\n\n<\/div>\n<\/div>\n<\/section>\n\n<section>\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">11. BASE DE FRENET<\/span>\n<h2>S\u00e9parer acc\u00e9l\u00e9ration tangentielle et normale.<\/h2>\n<\/div>\n\n<div class=\"grid\">\n\n<div class=\"card\">\n<h3>Vecteur tangent<\/h3>\n\n<div class=\"formula\">\nT\n<\/div>\n\n<p>\nDirig\u00e9 selon la vitesse.\n<\/p>\n<\/div>\n\n<div class=\"card\">\n<h3>Vecteur normal<\/h3>\n\n<div class=\"formula\">\nN\n<\/div>\n\n<p>\nDirig\u00e9 vers le centre de courbure.\n<\/p>\n<\/div>\n\n<div class=\"card\">\n<h3>D\u00e9composition<\/h3>\n\n<div class=\"formula\">\na = (dv\/dt)T + (v\u00b2\/Rc)N\n<\/div>\n<\/div>\n\n<div class=\"card\">\n<h3>Interpr\u00e9tation<\/h3>\n<p>\nLa composante tangentielle modifie la norme de v.\nLa composante normale modifie sa direction.\n<\/p>\n<\/div>\n\n<\/div>\n<\/div>\n<\/section>\n\n<section id=\"exercices\" style=\"background:#efede7\">\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">12. EXERCICES PROGRESSIFS<\/span>\n<h2>Passer de l&#8217;\u00e9quation au mouvement.<\/h2>\n<\/div>\n\n<div class=\"exercise\">\n<span class=\"level\">NIVEAU 1<\/span>\n\n<h3>Exercice 1 \u2014 Mouvement rectiligne<\/h3>\n\n<p>\nOn donne :\n<\/p>\n\n<div class=\"formula\">\nx(t)=3t\u00b2+2t-1\n<\/div>\n\n<p>\nD\u00e9terminer v(t) et a(t).\n<\/p>\n\n<button type=\"button\" class=\"btn gold\" onclick=\"mzaCinHint('cinHint1')\">\ud83d\udca1 INDICE<\/button>\n\n<div id=\"cinHint1\" class=\"hint\">\nD\u00e9rivez une premi\u00e8re fois pour obtenir la vitesse, puis une deuxi\u00e8me fois pour l&#8217;acc\u00e9l\u00e9ration.\n<\/div>\n<\/div>\n\n<div class=\"exercise\">\n<span class=\"level\">NIVEAU 2<\/span>\n\n<h3>Exercice 2 \u2014 Trajectoire<\/h3>\n\n<p>\nOn donne :\n<\/p>\n\n<div class=\"formula\">\nx(t)=2t<br>\ny(t)=t\u00b2\n<\/div>\n\n<p>\nD\u00e9terminer l&#8217;\u00e9quation cart\u00e9sienne de la trajectoire.\n<\/p>\n\n<button type=\"button\" class=\"btn gold\" onclick=\"mzaCinHint('cinHint2')\">\ud83d\udca1 INDICE<\/button>\n\n<div id=\"cinHint2\" class=\"hint\">\nExprimez t en fonction de x puis remplacez dans y(t).\n<\/div>\n<\/div>\n\n<div class=\"exercise\">\n<span class=\"level\">NIVEAU 3<\/span>\n\n<h3>Exercice 3 \u2014 Mouvement circulaire<\/h3>\n\n<p>\nUn point d\u00e9crit un cercle de rayon R avec vitesse angulaire constante \u03c9.\nD\u00e9terminer sa vitesse et son acc\u00e9l\u00e9ration.\n<\/p>\n\n<button type=\"button\" class=\"btn gold\" onclick=\"mzaCinHint('cinHint3')\">\ud83d\udca1 INDICE<\/button>\n\n<div id=\"cinHint3\" class=\"hint\">\nUtilisez les expressions en coordonn\u00e9es polaires avec r=R constant et \u03b8\u0307=\u03c9.\n<\/div>\n<\/div>\n\n<div class=\"exercise\">\n<span class=\"level\">NIVEAU PR\u00c9PA<\/span>\n\n<h3>Exercice 4 \u2014 Projectile<\/h3>\n\n<p>\nUn projectile est lanc\u00e9 depuis le sol avec une vitesse v\u2080\nsous l&#8217;angle \u03b1. D\u00e9terminer :\n<\/p>\n\n<ul>\n<li>le temps de vol ;<\/li>\n<li>la hauteur maximale ;<\/li>\n<li>la port\u00e9e horizontale.<\/li>\n<\/ul>\n\n<button type=\"button\" class=\"btn gold\" onclick=\"mzaCinHint('cinHint4')\">\ud83d\udca1 INDICE<\/button>\n\n<div id=\"cinHint4\" class=\"hint\">\nCommencez par utiliser la composante verticale de la vitesse pour la hauteur maximale, puis y(t)=0 pour le temps de vol.\n<\/div>\n<\/div>\n\n<\/div>\n<\/section>\n\n<section>\n<div class=\"wrap\">\n\n<div class=\"head\">\n<span class=\"kicker\">13. PROBLEM LAB<\/span>\n<h2>Mission : poursuite entre deux mobiles.<\/h2>\n<\/div>\n\n<div class=\"card\">\n\n<h3>Situation<\/h3>\n\n<p>\nUne voiture A passe \u00e0 l&#8217;origine \u00e0 t=0 avec une vitesse constante vA.\nDeux secondes plus tard, une voiture B d\u00e9marre depuis l&#8217;origine avec une acc\u00e9l\u00e9ration constante a.\n<\/p>\n\n<p>Votre mission :<\/p>\n\n<ol>\n<li>choisir une origine des temps commune ;<\/li>\n<li>\u00e9crire xA(t) ;<\/li>\n<li>\u00e9crire xB(t) en tenant compte du retard de d\u00e9marrage ;<\/li>\n<li>d\u00e9terminer l&#8217;instant o\u00f9 B rattrape A ;<\/li>\n<li>d\u00e9terminer la position du rattrapage ;<\/li>\n<li>comparer les vitesses des deux voitures \u00e0 cet instant ;<\/li>\n<li>interpr\u00e9ter physiquement le r\u00e9sultat.<\/li>\n<\/ol>\n\n<div class=\"actions\">\n<button type=\"button\" class=\"btn gold\" onclick=\"mzaCinHint('cinMission1')\">\ud83d\udca1 INDICE<\/button>\n<button type=\"button\" class=\"btn\" style=\"background:#06172c;color:#fff\" onclick=\"mzaCinHint('cinMission2')\">\ud83e\udde0 M\u00c9THODE<\/button>\n<\/div>\n\n<div id=\"cinMission1\" class=\"hint\">\nLa voiture B n&#8217;existe dans le mod\u00e8le de mouvement qu&#8217;\u00e0 partir de t=2 s. Son temps propre de mouvement est donc t-2.\n<\/div>\n\n<div id=\"cinMission2\" class=\"hint\">\nLe rattrapage se produit lorsque xA(t)=xB(t). Ne comparez pas directement les vitesses pour trouver l&#8217;instant de rencontre.\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 MOTION CHECK<\/span>\n<h2>Avant de valider une cin\u00e9matique.<\/h2>\n<\/div>\n\n<div class=\"method\">\n<div><b>A<\/b><span>REP\u00c8RE<\/span><\/div>\n<div><b>B<\/b><span>POSITION<\/span><\/div>\n<div><b>C<\/b><span>VITESSE<\/span><\/div>\n<div><b>D<\/b><span>ACC\u00c9L\u00c9RATION<\/span><\/div>\n<div><b>E<\/b><span>TRAJECTOIRE<\/span><\/div>\n<div><b>F<\/b><span>INTERPR\u00c9TATION<\/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\">14. QCM DE VALIDATION<\/span>\n<h2>Diagnostic Cin\u00e9matique CPGE.<\/h2>\n\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=\"cinQuiz\">\n\n<div class=\"question\">\n<strong>1. Le vecteur vitesse est :<\/strong>\n<label><input type=\"radio\" name=\"c1\" value=\"1\"> la d\u00e9riv\u00e9e du vecteur position<\/label>\n<label><input type=\"radio\" name=\"c1\" value=\"0\"> la d\u00e9riv\u00e9e de l&#8217;acc\u00e9l\u00e9ration<\/label>\n<label><input type=\"radio\" name=\"c1\" value=\"0\"> toujours constant<\/label>\n<label><input type=\"radio\" name=\"c1\" value=\"0\"> toujours radial<\/label>\n<\/div>\n\n<div class=\"question\">\n<strong>2. Dans un mouvement rectiligne uniforme :<\/strong>\n<label><input type=\"radio\" name=\"c2\" value=\"1\"> l&#8217;acc\u00e9l\u00e9ration est nulle<\/label>\n<label><input type=\"radio\" name=\"c2\" value=\"0\"> la vitesse est nulle<\/label>\n<label><input type=\"radio\" name=\"c2\" value=\"0\"> l&#8217;acc\u00e9l\u00e9ration est constante non nulle<\/label>\n<label><input type=\"radio\" name=\"c2\" value=\"0\"> la trajectoire est circulaire<\/label>\n<\/div>\n\n<div class=\"question\">\n<strong>3. Dans un mouvement circulaire uniforme :<\/strong>\n<label><input type=\"radio\" name=\"c3\" value=\"1\"> l&#8217;acc\u00e9l\u00e9ration est dirig\u00e9e vers le centre<\/label>\n<label><input type=\"radio\" name=\"c3\" value=\"0\"> l&#8217;acc\u00e9l\u00e9ration est nulle<\/label>\n<label><input type=\"radio\" name=\"c3\" value=\"0\"> la vitesse vectorielle est constante<\/label>\n<label><input type=\"radio\" name=\"c3\" value=\"0\"> le rayon varie lin\u00e9airement<\/label>\n<\/div>\n\n<div class=\"question\">\n<strong>4. En coordonn\u00e9es polaires, la vitesse vaut :<\/strong>\n<label><input type=\"radio\" name=\"c4\" value=\"1\"> \u1e59e\u1d63 + r\u03b8\u0307e\u03b8<\/label>\n<label><input type=\"radio\" name=\"c4\" value=\"0\"> r\u0308e\u1d63<\/label>\n<label><input type=\"radio\" name=\"c4\" value=\"0\"> r\u03b8e\u1d63<\/label>\n<label><input type=\"radio\" name=\"c4\" value=\"0\"> \u1e59e\u03b8 uniquement<\/label>\n<\/div>\n\n<div class=\"question\">\n<strong>5. La trajectoire d&#8217;un projectile sans frottement dans un champ de pesanteur uniforme est :<\/strong>\n<label><input type=\"radio\" name=\"c5\" value=\"1\"> une parabole<\/label>\n<label><input type=\"radio\" name=\"c5\" value=\"0\"> un cercle<\/label>\n<label><input type=\"radio\" name=\"c5\" value=\"0\"> une droite toujours<\/label>\n<label><input type=\"radio\" name=\"c5\" value=\"0\"> une ellipse forc\u00e9ment<\/label>\n<\/div>\n\n<div class=\"question\">\n<strong>6. Dans la base de Frenet, la composante normale de l&#8217;acc\u00e9l\u00e9ration est :<\/strong>\n<label><input type=\"radio\" name=\"c6\" value=\"1\"> v\u00b2\/Rc<\/label>\n<label><input type=\"radio\" name=\"c6\" value=\"0\"> dv\/dt<\/label>\n<label><input type=\"radio\" name=\"c6\" value=\"0\"> toujours nulle<\/label>\n<label><input type=\"radio\" name=\"c6\" value=\"0\"> \u00e9gale \u00e0 vRc<\/label>\n<\/div>\n\n<button type=\"button\" class=\"btn gold\" onclick=\"mzaCinScore()\">\nVALIDER MON QCM\n<\/button>\n\n<\/form>\n\n<div id=\"cinResult\"><\/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\">v = dr\/dt<\/div>\n\n<h2>D\u00e9crire correctement le mouvement avant d&#8217;expliquer sa cause.<\/h2>\n\n<p>\nRep\u00e8re, position, trajectoire, vitesse et acc\u00e9l\u00e9ration constituent\nles fondations de toute la m\u00e9canique. Une cin\u00e9matique bien pos\u00e9e\nrend la dynamique beaucoup plus simple.\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 mzaCinHint(id){\n const el=document.getElementById(id);\n if(!el)return;\n el.style.display = el.style.display===\"block\" ? \"none\" : \"block\";\n}\n\nfunction mzaCinScore(){\n const form=document.getElementById(\"cinQuiz\");\n const result=document.getElementById(\"cinResult\");\n\n let score=0;\n let complete=true;\n\n [\"c1\",\"c2\",\"c3\",\"c4\",\"c5\",\"c6\"].forEach(function(name){\n   const answer=form.querySelector('input[name=\"'+name+'\"]:checked');\n\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=\"Cin\u00e9matique \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 02 \u2022 PHYSIQUE CPGE D\u00e9crire.D\u00e9river. Interpr\u00e9ter. La cin\u00e9matique d\u00e9crit le mouvement sans chercher encore sa cause. Position, trajectoire, vitesse et acc\u00e9l\u00e9ration constituent le langage fondamental de toute la m\u00e9canique. \ud83d\udcda COMMENCER \ud83e\udde0 M\u00c9THODE \ud83e\udde9 EXERCICES \u2753 QCM 1. R\u00c9F\u00c9RENTIEL Un mouvement n&#8217;existe que relativement \u00e0 un observateur. R\u00e9f\u00e9rentiel Un r\u00e9f\u00e9rentiel associe un rep\u00e8re [&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-1575","page","type-page","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/maroczain.com\/scolaire.maroczain.com\/wp-json\/wp\/v2\/pages\/1575","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=1575"}],"version-history":[{"count":1,"href":"https:\/\/maroczain.com\/scolaire.maroczain.com\/wp-json\/wp\/v2\/pages\/1575\/revisions"}],"predecessor-version":[{"id":1577,"href":"https:\/\/maroczain.com\/scolaire.maroczain.com\/wp-json\/wp\/v2\/pages\/1575\/revisions\/1577"}],"wp:attachment":[{"href":"https:\/\/maroczain.com\/scolaire.maroczain.com\/wp-json\/wp\/v2\/media?parent=1575"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}