3 part hypothetical battery question

AI Thread Summary
The discussion focuses on a hypothetical scenario involving two capacitors: a charged 3.50 µF capacitor connected to a 13.0 V battery and an uncharged 4.44 µF capacitor. Participants emphasize the need to calculate the total stored energy before and after the capacitors are connected, as well as the change in energy. Key equations mentioned include the relationship between charge, voltage, and energy stored in a capacitor, specifically E=(1/2)CV^2. The importance of ensuring that the voltage across both capacitors is equal after connection is also highlighted. Overall, the thread seeks to clarify the calculations necessary for understanding energy transfer between the capacitors.
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Homework Statement


A 3.50 µF capacitor is charged by a 13.0 V battery. It is disconnected from the battery and then connected to an uncharged 4.44 µF capacitor (Fig. 17-29).

17_28.gif

Figure 17-29
Determine the total stored energy at the following points in time.

(a) before the two capacitors are connected
____ J
(b) after they are connected
____ J
(c) What is the change in energy?
____ J


Homework Equations



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The Attempt at a Solution


No idea
 
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Didn't you find any relevant equation about the capacitor in your textbook?
For example, the relation between capacitor, charge stored in the capacitor and voltage across the plates of the capacitor. What is the expression for the energy stored in the capacitor?
 
After the capacitors are connected, the charges on the two capacitors must sum to the initial charge on C1. The voltage across the two capacitors must be equal. Write out equations representing these two facts, and solve for the voltage. Then remember that E=(1/2)CV^2.
 
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