Quiz — Série onde (2).pdf

Question 1 sur 10 20:00

[{"id":98630,"question":"Quelle grandeur physique reste inchangée lors du passage d'une onde d'un milieu à un autre ?","option_a":"La célérité","option_b":"La fréquence","option_c":"L'amplitude","option_d":"La longueur d'onde","option_e":"","option_f":"","bonne_reponse":"b","explication":"La fréquence d'une onde reste constante lors d'un changement de milieu, car elle dépend de la source émettrice.","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 célérité\", \"b\": \"La fréquence\", \"c\": \"L'amplitude\", \"d\": \"","_debug_options_count":4},{"id":98631,"question":"Les ondes sonores sont des ondes transversales.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"b","explication":"Les ondes sonores sont des ondes longitudinales, car la perturbation se fait dans la même direction que la propagation.","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":98632,"question":"Quelle est l'unité de la fréquence dans le système international ?","option_a":"Hertz (Hz)","option_b":"Mètre (m)","option_c":"Seconde (s)","option_d":"Newton (N)","option_e":"","option_f":"","bonne_reponse":"a","explication":"La fréquence s'exprime en Hertz (Hz), équivalent à s⁻¹.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"a\", \"options\": {\"a\": \"Hertz (Hz)\", \"b\": \"Mètre (m)\", \"c\": \"Seconde (s)\", \"d\": \"Newton ","_debug_options_count":4},{"id":98633,"question":"Une onde électromagnétique peut se propager dans le vide.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"a","explication":"Les ondes électromagnétiques, comme la lumière, se propagent dans le vide à la célérité de 3×10⁸ m\/s.","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":98634,"question":"Quelle relation lie la longueur d'onde (λ), la célérité (v) et la fréquence (f) ?","option_a":"λ = v × f","option_b":"v = λ × f","option_c":"f = λ \/ v","option_d":"v = f \/ λ","option_e":"","option_f":"","bonne_reponse":"b","explication":"La formule correcte est v = λ × f, où v est la célérité, λ la longueur d'onde et f la fréquence.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"λ = v × f\", \"b\": \"v = λ × f\", \"c\": \"f = λ \/ v\", \"d\": \"v = f ","_debug_options_count":4},{"id":98635,"question":"Le phénomène de réflexion d'une onde dépend de la nature du milieu.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"b","explication":"La réflexion dépend des propriétés des milieux (impédance acoustique pour les ondes sonores, indice de réfraction pour la lumière).","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":98636,"question":"Quelle est la longueur d'onde d'une onde sonore de fréquence 500 Hz se propageant dans l'air (c = 340 m\/s) ?","option_a":"0,68 m","option_b":"1,47 m","option_c":"0,17 m","option_d":"340 m","option_e":"","option_f":"","bonne_reponse":"a","explication":"λ = v \/ f = 340 \/ 500 = 0,68 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\": \"0,68 m\", \"b\": \"1,47 m\", \"c\": \"0,17 m\", \"d\": \"340 m\"}}","_debug_options_count":4},{"id":98637,"question":"Les ondes radio sont des ondes mécaniques.","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"b","explication":"Les ondes radio sont des ondes électromagnétiques, car elles se propagent dans le vide et ne nécessitent pas de milieu matériel.","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":98638,"question":"Quelle propriété des ondes est responsable de la formation des ombres ?","option_a":"La diffraction","option_b":"La réflexion","option_c":"La réfraction","option_d":"L'absorption","option_e":"","option_f":"","bonne_reponse":"b","explication":"La réflexion des ondes lumineuses sur un objet opaque crée des zones d'ombre.","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 diffraction\", \"b\": \"La réflexion\", \"c\": \"La réfraction\", \"d\"","_debug_options_count":4},{"id":98639,"question":"Une onde de fréquence 2 kHz a une période de :","option_a":"0,0005 s","option_b":"0,002 s","option_c":"0,5 s","option_d":"2 s","option_e":"","option_f":"","bonne_reponse":"b","explication":"La période T est l'inverse de la fréquence : T = 1\/f = 1\/2000 = 0,0005 s.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0,"_debug_answer_data_type":"string","_debug_answer_data_preview":"{\"correct\": \"b\", \"options\": {\"a\": \"0,0005 s\", \"b\": \"0,002 s\", \"c\": \"0,5 s\", \"d\": \"2 s\"}}","_debug_options_count":4}]