Where Did the .25J of Energy Go?

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SUMMARY

The discussion centers on the energy distribution in a circuit involving a 100V battery and two 100 micro-Farad capacitors. Initially, the first capacitor stores 0.5J of energy. After connecting a second capacitor in parallel, the total energy remains 0.5J, but is divided equally, resulting in 0.25J stored in each capacitor. This phenomenon illustrates the principle of conservation of energy, confirming that energy is neither created nor destroyed, but redistributed within the circuit.

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A 100V battery is connected to a 100 micro-Farad capacitor. The stored energy is given by U=1/2C(delta V)^2. Which is 0.5J. The battery is taken out of the circuit and the capacitor is connected to another 100 micro-Farad capacitor. Using the same equation above and considering the potential difference for each capacitor is then 50V you get .125J for each capacitor. We were told to assume there was no electrical resistance in this circuit.

My question is...were did the .25J of energy disappear to?

Thanks for the help!
 
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...where did the .25J of energy disappear to?
Radiated away as electromagnetic waves.
 


The .25J of energy did not disappear, it was divided between the two capacitors. When the battery was connected to the first capacitor, it stored 0.5J of energy. When the capacitors were connected in parallel, the total stored energy was still 0.5J, but it was now divided between the two capacitors, with each one storing 0.25J. This is because the total capacitance in the circuit increased, causing the potential difference across each capacitor to decrease. Therefore, the energy stored in each capacitor decreased proportionally. This is known as the principle of conservation of energy, which states that energy cannot be created or destroyed, only transferred or transformed. In this case, the energy was transferred from one capacitor to the other.
 

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