Quiz — Hamdi - Oscillations libres non amorties.pdf

Question 1 sur 10 20:00

[{"id":57687,"question":"Quelle équation différentielle caractérise un mouvement harmonique simple ?","option_a":"d²x\/dt² + ω²x = 0","option_b":"d²x\/dt² + γ(dx\/dt) + ω²x = 0","option_c":"d²x\/dt² = -kx\/m","option_d":"d²x\/dt² + kx = 0","option_e":"","option_f":"","bonne_reponse":"a","explication":"L'équation différentielle d'un mouvement harmonique simple est d²x\/dt² + ω²x = 0, où ω est la pulsation propre du système.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"a\", \"options\": {\"a\": \"d²x\/dt² + ω²x = 0\", \"b\": \"d²x\/dt² + γ(dx\/dt) + ω²x = 0\",","_debug_options_count":4},{"id":57688,"question":"La période T d'un système oscillant est-elle indépendante de l'amplitude ?","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"a","explication":"Pour un mouvement harmonique simple, la période T est indépendante de l'amplitude (isochronisme des oscillations).","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"a\", \"options\": {\"a\": \"Vrai\", \"b\": \"Faux\", \"c\": \"\", \"d\": \"\"}}","_debug_options_count":4},{"id":57689,"question":"Quelle est la relation entre la fréquence f et la période T d'un oscillateur ?","option_a":"f = T","option_b":"f = 1\/T","option_c":"f = 2πT","option_d":"f = T²","option_e":"","option_f":"","bonne_reponse":"b","explication":"La fréquence f est l'inverse de la période T : f = 1\/T.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"f = T\", \"b\": \"f = 1\/T\", \"c\": \"f = 2πT\", \"d\": \"f = T²\"}}","_debug_options_count":4},{"id":57690,"question":"Dans un système masse-ressort horizontal, quelle force s'oppose au mouvement ?","option_a":"La force de frottement","option_b":"La force élastique du ressort","option_c":"La force gravitationnelle","option_d":"La force normale","option_e":"","option_f":"","bonne_reponse":"b","explication":"La force élastique du ressort, donnée par F = -kx, s'oppose au mouvement et est responsable des oscillations.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"La force de frottement\", \"b\": \"La force élastique du ressort\", \"","_debug_options_count":4},{"id":57691,"question":"L'énergie mécanique totale d'un système oscillant non amorti est-elle constante ?","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"a","explication":"Oui, en l'absence de frottements, l'énergie mécanique totale (cinétique + potentielle) se conserve.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"a\", \"options\": {\"a\": \"Vrai\", \"b\": \"Faux\", \"c\": \"\", \"d\": \"\"}}","_debug_options_count":4},{"id":57692,"question":"Quelle est l'expression de la pulsation ω d'un pendule simple de longueur L ?","option_a":"ω = √(g\/L)","option_b":"ω = √(L\/g)","option_c":"ω = 2π√(L\/g)","option_d":"ω = g\/L","option_e":"","option_f":"","bonne_reponse":"a","explication":"La pulsation ω d'un pendule simple est donnée par ω = √(g\/L), où g est l'accélération due à la gravité.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"a\", \"options\": {\"a\": \"ω = √(g\/L)\", \"b\": \"ω = √(L\/g)\", \"c\": \"ω = 2π√(L\/g)\", \"d","_debug_options_count":4},{"id":57693,"question":"Un ressort de constante de raideur k = 100 N\/m est étiré de 5 cm. Quelle est la force élastique exercée ?","option_a":"5 N","option_b":"0,5 N","option_c":"50 N","option_d":"2 N","option_e":"","option_f":"","bonne_reponse":"a","explication":"La force élastique est donnée par F = -kx. Ici, F = 100 × 0,05 = 5 N (en valeur absolue).","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"a\", \"options\": {\"a\": \"5 N\", \"b\": \"0,5 N\", \"c\": \"50 N\", \"d\": \"2 N\"}}","_debug_options_count":4},{"id":57694,"question":"La solution générale d'un mouvement harmonique simple est-elle toujours de la forme x(t) = A cos(ωt + φ) ?","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"a","explication":"Oui, la solution générale d'un mouvement harmonique simple est x(t) = A cos(ωt + φ), où A est l'amplitude, ω la pulsation et φ la phase initiale.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"a\", \"options\": {\"a\": \"Vrai\", \"b\": \"Faux\", \"c\": \"\", \"d\": \"\"}}","_debug_options_count":4},{"id":57695,"question":"Quel paramètre physique détermine principalement la fréquence d'oscillation d'un système masse-ressort ?","option_a":"La masse m","option_b":"La constante de raideur k","option_c":"L'amplitude initiale","option_d":"La longueur du ressort","option_e":"","option_f":"","bonne_reponse":"b","explication":"La fréquence d'oscillation dépend principalement de la constante de raideur k et de la masse m : f = (1\/2π)√(k\/m).","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"La masse m\", \"b\": \"La constante de raideur k\", \"c\": \"L'amplitude ","_debug_options_count":4},{"id":57696,"question":"Si l'amplitude d'un oscillateur double, que devient son énergie mécanique totale ?","option_a":"Elle reste la même","option_b":"Elle double","option_c":"Elle quadruple","option_d":"Elle diminue de moitié","option_e":"","option_f":"","bonne_reponse":"c","explication":"L'énergie mécanique totale est proportionnelle au carré de l'amplitude : E = ½kA². Si A double, E quadruple.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"c\", \"options\": {\"a\": \"Elle reste la même\", \"b\": \"Elle double\", \"c\": \"Elle quadruple\", ","_debug_options_count":4}]