17 1 I )Le condensateur 1 (dilectrique) . | | 2 . . . : . - ( 1 ) . ic . A B . A qA B qB qB = - qA A Q = qA = - qB. - ( 2 ) . id . qA | qB| 3 - i = q / t q coulombs(C) t (s) - i = dq / dt4 1.4 c G V K . I = 1mA . - t = 0 10 . uAB = f(t) . K . qA I K uAB . .2.4 t(s) 0 10 20 30 40 50uAB (V)0 2,3 4,6 6,9 9,2 11,5 uAB = f(t) s / V 23 , 0505 , 11t) u (KAB= =AA= t . I qA = t . K uAB = KIuqABA= AB Au .KIq = - CKI= AB Au . C q = C ( F ) F 10 . 34 , 423 , 010C33= = : 1mF= 10-3F 1F = 10-6 F1nF = 10-9 F 1pF = 10-12 F 5 1.5 118 C1C2 uAB. q1 C1q2 C2q .AB AB 2 1 AB 2 AB 1 2 1u . C u ). C C ( u . C u . C q q q = + = + = + = C1C2 C = C1 + C2 C1C2. . . . Cn C = C1 + C2 + . . .+Cn 2.5 C1C2 uAB. q = q1 = q2 uAB = uAD + uDB1AD2DBCquCqu = = 2 1ABCqCqu + = CquAB = 2 1C1C1C1+ = C1C2 C 2 1C1C1C1+ = C1C2. . . Cn C n 2 1C1...C1C1C1+ + + = .II ) RC rponse dun diple RC un chelon du tension 1 tude exprimentale RC R C . u = 0 u = E u = E u = 0 . RC : E = 5V R = 1kO C = 20F K ( 1 ) Logger Pro 3 uAB . (t 5 t( uC = E 1 t = R.C . 2 t : - ( 1 : ) t t = 0 uC = E . - ( 2 ) : t = t uC = 0,63.E . t .3 . K ( 2 ) Logger Pro 3 uC . 219 - ( 1 : ) t t = 0 uC = 0 ( 2 ) : t = t UC = 0,37.E t . 2 t t . R C E 1 t E .2 - t R.3 t C . 1 t = RC t = 1000.20.10-6 = 20.10-3s = 20ms2 : 0,63E t = 20ms3 100ms = 5t . 1 . 0,37E t = 20ms . 2 t = t . R C E 1 E . 2 R t . R . 3 C t . C.2 1.2 uMN = uMA + uAB uMN = uR + uC( 1 ) uMN = EuR = R.i CquC = . dtdqi =Cidtdq.C1dtdudtdu. C iC c= = : =( 1 ) E = R.i + uC. udtduC . R ECC+ = uC ( 2 )RCERCudtduC C= + b ae utC+ =o a b o .( 2 ) RCERCbeRCae aRCERCbae )RC1(t t t= + + o = + o o o o 0RC1RCERCb= o = o = RC b = E uC = 0 a + b = 0 a = - E : ) e 1 ( E ) e 1 ( E utRCtCt = = : t RC ( s ) t = RC .2.2 uR + uC = 0 uR = R.i = R.dq/dt 20 q = C.uCdtduRC uCR = 0 udtduRCCC= + uC : 0RCudtduC C= + ( 3 ) b ae utC+ =o a b o .( 3 ) 0RCbeRCae a 0RCbae )RC1(t t t= + + o = + o o o o

0RC1 0RCb= o = RC1= o b = 0 t = 0 uC = E 0ae E = a = E t = =tRCtCe . E Ee u t = RC .3.2 q = C.uC : RERCqdtdq= + 0RCqdtdq= + . : ) e 1 ( EC qtt = t=te . EC qIII ) Energie stocke dans un condensateur1 C i u . P = u.i dtdqi = q = C.u dt)Cq21( ddtdq. q .C1P2= = dtdEPe= t :Cq21E2e = q = Cu t :2eCu21E = 2 C = 100F R = 100O M . ( 1 ) ( 2 )1 2 E G 1 Ee .2 C E G Ee . www.maths-physique.comwww.physique-maths.comPr: HALIB AZIZ