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    Hi. This capacitance problem's gotten me confused. Please help!
    A capacitor A of capacitance 4 microfarads is charged to a p.d of 20 V. An uncharged capacitor B of capacitance 2 microfarads is then connected in parallel with A. What is the (a) the energy initially stored in A (b) The pd acros A after B has been connected (c) the energy finally stored in A and B

    I got .8 mJ for the first one but for part B, I had 20 V but it's supposed to be 14 ..i tried to figure how they got that with the ratio but i'm confused..isn't the voltage across parallel capacitors supposed to be the same?

    Thanks 2 ne1 who replies to this post!
 
 
 
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