Quiz — TD 10 - Comportement cinématique des systèmes.pdf

Question 1 sur 10 20:00

[{"id":8375,"question":"Quel paramètre cinématique reste constant dans un mouvement de translation rectiligne uniforme ?","option_a":"La vitesse","option_b":"L'accélération","option_c":"La trajectoire","option_d":"La position","option_e":"","option_f":"","bonne_reponse":"a","explication":"Dans un mouvement de translation rectiligne uniforme, la vitesse est constante car il n'y a pas d'accélération (a = 0).","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"a\", \"options\": {\"a\": \"La vitesse\", \"b\": \"L'accélération\", \"c\": \"La trajectoire\", \"d\":","_debug_options_count":4},{"id":8376,"question":"La trajectoire d'un point matériel est toujours une droite.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"b","explication":"La trajectoire peut être une droite (mouvement rectiligne) ou une courbe (mouvement curviligne), selon le système étudié.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"Vrai\", \"b\": \"Faux\", \"c\": \"\", \"d\": \"\"}}","_debug_options_count":4},{"id":8377,"question":"Quelle formule permet de calculer l'accélération moyenne d'un système ?","option_a":"a = Δv \/ Δt","option_b":"a = v × t","option_c":"a = d \/ t²","option_d":"a = F \/ m","option_e":"","option_f":"","bonne_reponse":"a","explication":"L'accélération moyenne se calcule par le rapport de la variation de vitesse (Δv) sur le temps écoulé (Δt).","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"a\", \"options\": {\"a\": \"a = Δv \/ Δt\", \"b\": \"a = v × t\", \"c\": \"a = d \/ t²\", \"d\": \"a = ","_debug_options_count":4},{"id":8378,"question":"Un système en rotation autour d'un axe fixe a une vitesse angulaire ω = 5 rad\/s. Quelle est sa vitesse linéaire v à 2 mètres de l'axe ?","option_a":"v = 2 m\/s","option_b":"v = 5 m\/s","option_c":"v = 10 m\/s","option_d":"v = 2.5 m\/s","option_e":"","option_f":"","bonne_reponse":"c","explication":"La vitesse linéaire v est donnée par v = ω × r, soit v = 5 × 2 = 10 m\/s.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"c\", \"options\": {\"a\": \"v = 2 m\/s\", \"b\": \"v = 5 m\/s\", \"c\": \"v = 10 m\/s\", \"d\": \"v = 2.5 m\/","_debug_options_count":4},{"id":8379,"question":"L'accélération centripète est toujours dirigée vers l'extérieur de la trajectoire.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"b","explication":"L'accélération centripète est dirigée vers le centre de la trajectoire courbe, pas vers l'extérieur.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"Vrai\", \"b\": \"Faux\", \"c\": \"\", \"d\": \"\"}}","_debug_options_count":4},{"id":8380,"question":"Quel type de mouvement a une accélération nulle ?","option_a":"Mouvement accéléré","option_b":"Mouvement uniforme","option_c":"Mouvement circulaire","option_d":"Mouvement de chute libre","option_e":"","option_f":"","bonne_reponse":"b","explication":"Un mouvement uniforme a une vitesse constante, donc une accélération nulle (a = 0).","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"Mouvement accéléré\", \"b\": \"Mouvement uniforme\", \"c\": \"Mouvemen","_debug_options_count":4},{"id":8381,"question":"Dans un mouvement de rotation, la vitesse linéaire d'un point dépend de :","option_a":"Sa masse","option_b":"Sa distance à l'axe de rotation","option_c":"Sa couleur","option_d":"Son altitude","option_e":"","option_f":"","bonne_reponse":"b","explication":"La vitesse linéaire v dépend de la vitesse angulaire ω et de la distance r à l'axe : v = ω × r.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"Sa masse\", \"b\": \"Sa distance à l'axe de rotation\", \"c\": \"Sa coul","_debug_options_count":4},{"id":8382,"question":"Un mobile part du repos et atteint une vitesse de 20 m\/s en 4 secondes. Quelle est son accélération moyenne ?","option_a":"5 m\/s²","option_b":"8 m\/s²","option_c":"10 m\/s²","option_d":"4 m\/s²","option_e":"","option_f":"","bonne_reponse":"a","explication":"L'accélération moyenne est a = Δv \/ Δt = (20 - 0) \/ 4 = 5 m\/s².","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 m\/s²\", \"b\": \"8 m\/s²\", \"c\": \"10 m\/s²\", \"d\": \"4 m\/s²\"}}","_debug_options_count":4},{"id":8383,"question":"La trajectoire d'un projectile lancé horizontalement est toujours une parabole.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"a","explication":"Sous l'effet de la gravité, la trajectoire d'un projectile est parabolique si on néglige les frottements.","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":8384,"question":"Quelle grandeur cinématique est représentée par la dérivée de la position par rapport au temps ?","option_a":"L'accélération","option_b":"La vitesse","option_c":"La force","option_d":"L'énergie","option_e":"","option_f":"","bonne_reponse":"b","explication":"La dérivée de la position (x) par rapport au temps (t) donne la vitesse instantanée : v = dx\/dt.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"L'accélération\", \"b\": \"La vitesse\", \"c\": \"La force\", \"d\": \"L'é","_debug_options_count":4}]