Charge on capacitors, total energy

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When a 20 microfarad capacitor charged to 10V is connected to an uncharged 20 microfarad capacitor, both capacitors reach a charge of 10 microcoulombs. The total energy stored in this configuration is calculated to be 1 millijoule. If the second capacitor is instead rated at 30 microfarads, the charge remains at 10 microcoulombs, but the total energy increases to 1.5 millijoules. This demonstrates that energy storage in capacitors is directly proportional to capacitance. Reliable resources for further information on capacitors include All About Circuits and Electronics Tutorials.
kat_r
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Can some one please help me with this question:
A 20 microfarrad capacitor is charged to 10V and isolated. A second uncharged 20 microfarrad capacitor is now connected to the plates of the other. The capacitors rapidly come to the same pd between their plates. What is the charge on each capacitor now? What is the total energy stored in the two capacitors? Comment on your answer. Now repeat with the second capacitor rated at 30 microfarrads.

While we're on the subject of capacitors does anyone know any good websites about capacitors?
 
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Maybe:
http://scienceworld.wolfram.com
Or if you're looking for specifics about Capacitors I could always look it up in the books I got... or you could Google. :)
 


Once the capacitors are connected, the charge on each capacitor will be the same, as they are in parallel. This means that the charge on each capacitor will be 10 microcoulombs (since Q = CV, where Q is charge, C is capacitance, and V is voltage).

The total energy stored in the two capacitors can be calculated by using the formula for energy stored in a capacitor: E = 1/2 * CV^2. Plugging in the values, we get a total energy of 1 millijoule (0.5 * 20 x 10^-6 F * 10^2 V).

If we repeat the scenario with the second capacitor rated at 30 microfarads, the charge on each capacitor will still be 10 microcoulombs, but the total energy stored will now be 1.5 millijoules (0.5 * 30 x 10^-6 F * 10^2 V). This shows that the energy stored in a capacitor is directly proportional to its capacitance.

As for good websites about capacitors, some reliable sources include All About Circuits, Electronics Tutorials, and SparkFun. These websites provide comprehensive information about capacitors, including their types, uses, and calculations.
 
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