Find the charge stored on each capacitor in Figure 1824 C1

Find the charge stored on each capacitor in Figure 18.24 (C_1 = 28.0 muF, C_2 = 4.50 muF) when a 1.41 V battery is connected to the combination. C_1______ C C_2_______ C 0.300 muF capacitor_________ C What energy is stored in each capacitor? C_1_________ J C_2________ J 0.300 muF capacitor______ J

Solution

C1 and C2 are in parallel

The parallel capacitance is , C=C1+C2=(28+4.5) uF=32.5 uF

Now capacitor c=.30 uF and C is in series

So total capacitance is C0=.30*C/(.30+C) uF=(32.5*.30)/(32.5+.30) uF=.297 uF

Now voltage V=1.41V

So, Charge Q=C0*V=.297*1.41 uC=0.41877 uC

So voltage at .30uF capacitor is Q/.30 V=1.3959 V

So,energy(E)=1/2CV^2=.3*1.3959*1.3959/2 uJ=0.292 uJ

Voltage at C1 is Q/C1=0.015 V

Energy(E1)=28*0.015*0.015/2 uJ=0.00315 uJ

Voltage at C2 is Q/C2=0.09306 V

Energy(E2)=4.5*0.09306*0.09306/2 uJ=0.0195 uJ