Quiz — 63fa29daf0ca2_énoncé_Onde mécaniques progressive_Série_2 (2).pdf

Question 1 sur 10 20:00

[{"id":81859,"question":"Quelle grandeur physique caractérise la distance parcourue par une onde en une seconde ?","option_a":"A. Période","option_b":"B. Fréquence","option_c":"C. Célérité","option_d":"D. Amplitude","option_e":"","option_f":"","bonne_reponse":"c","explication":"La célérité (ou vitesse de propagation) mesure la distance parcourue par l'onde par unité de temps, exprimée en 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\": \"A. Période\", \"b\": \"B. Fréquence\", \"c\": \"C. Célérité\", \"d\": \"","_debug_options_count":4},{"id":81860,"question":"Une onde mécanique peut se propager dans le vide.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"b","explication":"Les ondes mécaniques nécessitent un milieu matériel (solide, liquide ou gaz) pour se propager. Le vide ne permet pas leur transmission.","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":81861,"question":"Si une onde parcourt 1,5 m en 0,3 s, quelle est sa célérité ?","option_a":"A. 0,2 m\/s","option_b":"B. 5 m\/s","option_c":"C. 4,5 m\/s","option_d":"D. 0,5 m\/s","option_e":"","option_f":"","bonne_reponse":"c","explication":"Célérité = distance \/ temps = 1,5 m \/ 0,3 s = 5 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\": \"A. 0,2 m\/s\", \"b\": \"B. 5 m\/s\", \"c\": \"C. 4,5 m\/s\", \"d\": \"D. 0,5 m\/s","_debug_options_count":4},{"id":81862,"question":"La période d'une onde est de 0,02 s. Quelle est sa fréquence ?","option_a":"A. 0,02 Hz","option_b":"B. 50 Hz","option_c":"C. 20 Hz","option_d":"D. 0,5 Hz","option_e":"","option_f":"","bonne_reponse":"b","explication":"Fréquence = 1 \/ période = 1 \/ 0,02 = 50 Hz.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"A. 0,02 Hz\", \"b\": \"B. 50 Hz\", \"c\": \"C. 20 Hz\", \"d\": \"D. 0,5 Hz\"}}","_debug_options_count":4},{"id":81863,"question":"Le retard d'une onde est toujours positif.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"a","explication":"Le retard est une durée, donc toujours positif ou nul (Δt ≥ 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\": \"Vrai\", \"b\": \"Faux\", \"c\": \"\", \"d\": \"\"}}","_debug_options_count":4},{"id":81864,"question":"Quelle relation lie la longueur d'onde (λ), la célérité (v) et la période (T) ?","option_a":"A. λ = v × T","option_b":"B. λ = v \/ T","option_c":"C. λ = T \/ v","option_d":"D. λ = v + T","option_e":"","option_f":"","bonne_reponse":"a","explication":"La longueur d'onde est égale au produit de la célérité par la période (λ = v × T).","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. λ = v × T\", \"b\": \"B. λ = v \/ T\", \"c\": \"C. λ = T \/ v\", \"d\":","_debug_options_count":4},{"id":81865,"question":"Une onde mécanique a une célérité de 340 m\/s et une fréquence de 170 Hz. Quelle est sa longueur d'onde ?","option_a":"A. 0,5 m","option_b":"B. 2 m","option_c":"C. 57 800 m","option_d":"D. 0,003 m","option_e":"","option_f":"","bonne_reponse":"a","explication":"Longueur d'onde = célérité \/ fréquence = 340 \/ 170 = 2 m.","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. 0,5 m\", \"b\": \"B. 2 m\", \"c\": \"C. 57 800 m\", \"d\": \"D. 0,003 m\"}}","_debug_options_count":4},{"id":81866,"question":"L'amplitude d'une onde mécanique dépend de la fréquence.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"b","explication":"L'amplitude est indépendante de la fréquence ; elle dépend de l'énergie transportée par l'onde.","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":81867,"question":"Si on double la fréquence d'une onde, que devient sa période ?","option_a":"A. Elle double","option_b":"B. Elle reste la même","option_c":"C. Elle est divisée par 2","option_d":"D. Elle est multipliée par 4","option_e":"","option_f":"","bonne_reponse":"c","explication":"La période est l'inverse de la fréquence (T = 1\/f). Si f est multipliée par 2, T est divisée par 2.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"c\", \"options\": {\"a\": \"A. Elle double\", \"b\": \"B. Elle reste la même\", \"c\": \"C. Elle est","_debug_options_count":4},{"id":81868,"question":"Quelle grandeur physique reste constante lors de la propagation d'une onde dans un milieu homogène ?","option_a":"A. L'amplitude","option_b":"B. La célérité","option_c":"C. La fréquence","option_d":"D. La longueur d'onde","option_e":"","option_f":"","bonne_reponse":"b","explication":"Dans un milieu homogène, la célérité de l'onde reste constante, tandis que l'amplitude peut diminuer (atténuation).","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"A. L'amplitude\", \"b\": \"B. La célérité\", \"c\": \"C. La fréquence","_debug_options_count":4}]