- #1

Krushnaraj Pandya

Gold Member

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## Homework Statement

Two capacitors of 1 and 2 micro-farad respectively are each charged by being connected across a 5 V battery. They are disconnected from the battery and then connected to each other with resistive wires so that plates of opposite charge are connected together. What will be the magnitude of the final voltage across the 2 micro-farad capacitor?

## Homework Equations

All applicable to capacitance

## The Attempt at a Solution

First I though that after being charged, both have a potential 5 V...connecting them shouldn't change anything but then I realized that since E is inverted for one capacitor because of connecting reverse polarities, V will be -5 V for one and 5 V for the other (I assumed 1 mF capacitor to have 5 V) then conserving charge for positive plate of 1 mF and negative plate of 2 mF capacitor, I wrote C1V1-C2v2=C1V-C2V replacing; 5-(-10)=1V-2V, so -15=V which is an absurd result. Where am I going wrong, I'd appreciate some help