Testez vos connaissances sur le dipôle RC en Terminale Physique

Question 1 sur 10 10:00

[{"id":11108,"question":"Quelle est l'expression de la tension aux bornes du condensateur lors de sa charge ?","option_a":"U(t) = E × (1 - e^(-t\/τ))","option_b":"U(t) = E × e^(-t\/τ)","option_c":"U(t) = R × I(t)","option_d":"U(t) = Q\/C","option_e":"","option_f":"","bonne_reponse":"A","explication":"La tension aux bornes du condensateur lors de la charge suit la loi U(t) = E × (1 - e^(-t\/τ)), où E est la tension du générateur et τ = RC la constante de temps.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":11109,"question":"La constante de temps τ d'un circuit RC dépend-elle de la tension d'alimentation ?","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"B","explication":"La constante de temps τ = R × C ne dépend que de la résistance R et de la capacité C, pas de la tension d'alimentation.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":11110,"question":"Quelle est l'unité de la constante de temps τ ?","option_a":"Seconde (s)","option_b":"Farad (F)","option_c":"Ohm (Ω)","option_d":"Volt (V)","option_e":"","option_f":"","bonne_reponse":"A","explication":"La constante de temps τ s'exprime en secondes (s), car τ = R (en Ω) × C (en F) et Ω × F = s.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":11111,"question":"Lors de la décharge d'un condensateur, la tension à ses bornes :","option_a":"Diminue exponentiellement","option_b":"Augmente linéairement","option_c":"Reste constante","option_d":"Oscille","option_e":"","option_f":"","bonne_reponse":"A","explication":"Lors de la décharge, la tension aux bornes du condensateur diminue exponentiellement selon U(t) = U₀ × e^(-t\/τ).","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":11112,"question":"L'énergie stockée dans un condensateur est proportionnelle :","option_a":"À la tension U","option_b":"Au carré de la tension U²","option_c":"À l'intensité I","option_d":"À la résistance R","option_e":"","option_f":"","bonne_reponse":"B","explication":"L'énergie stockée E = ½ × C × U² est proportionnelle au carré de la tension U aux bornes du condensateur.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":11113,"question":"Un circuit RC série peut-il être utilisé pour filtrer un signal électrique ?","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"A","explication":"Oui, un circuit RC série est un filtre passe-bas naturel, atténuant les hautes fréquences et laissant passer les basses fréquences.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":11114,"question":"Quelle est la valeur de la constante de temps τ pour R = 10 kΩ et C = 1 µF ?","option_a":"10 ms","option_b":"100 ms","option_c":"1 ms","option_d":"1 s","option_e":"","option_f":"","bonne_reponse":"A","explication":"τ = R × C = 10 000 Ω × 1 × 10⁻⁶ F = 0,01 s = 10 ms.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":11115,"question":"La charge d'un condensateur est-elle instantanée ?","option_a":"Vrai","option_b":"Faux","option_c":"","option_d":"","option_e":"","option_f":"","bonne_reponse":"B","explication":"Non, la charge d'un condensateur prend un temps fini, lié à la constante de temps τ = RC.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":11116,"question":"Quelle relation lie la charge Q, la capacité C et la tension U aux bornes d'un condensateur ?","option_a":"Q = C × U","option_b":"Q = U \/ C","option_c":"Q = ½ × C × U²","option_d":"Q = R × I","option_e":"","option_f":"","bonne_reponse":"A","explication":"La charge Q d'un condensateur est donnée par Q = C × U, où C est la capacité et U la tension.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0},{"id":11117,"question":"Quel est l'effet d'une augmentation de la résistance R sur la constante de temps τ ?","option_a":"τ augmente","option_b":"τ diminue","option_c":"τ reste inchangée","option_d":"τ devient nulle","option_e":"","option_f":"","bonne_reponse":"A","explication":"Une augmentation de R entraîne une augmentation de τ = R × C, car τ est directement proportionnelle à R.","points":1,"type":"qcm","actif":1,"section_id":null,"ordre":0}]