Find Final Voltage of Parallel Capacitors

AI Thread Summary
To find the final voltage across two parallel capacitors, first calculate the total charge by adding the charges of both capacitors, resulting in 376 μC. The total capacitance is the sum of the individual capacitances, yielding 159 μF. The final voltage is then determined by dividing the total charge by the total capacitance, giving a final voltage of approximately 2.36 V. The discussion highlights confusion regarding the concept of initial voltage, emphasizing that it is not relevant in this scenario. The focus remains on using the total charge and capacitance to find the final voltage after connecting the capacitors in parallel.
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Homework Statement



Two capacitors of 34.0 μF and 125 μF are separately charged to 126 μC and 250 μC, respectively. They are then attached in parallel so that the + plate of one goes to the - plate of the other, and vice versa. Determine the final voltage across the two plates.

Homework Equations



C=Q/Vc

The Attempt at a Solution



I calculated the change in voltage by adding Q1 and Q2 and then dividing by the sum of C1 and C2. (126+250)/(34+125)=2.36 V. How do I find the initial voltage so that I can get the final voltage?
 
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Note how the 2 caps are attached to each other. "Initial voltage" does not seem like a relevant concept.
 

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