Is the Energy Stored in a Capacitor Really QV Instead of QV/2?

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Clara Chung
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Homework Statement
Attached below. I want to check whether my answer is right because the model answer is 0.576 mJ. Thank you.
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241073
 
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0.288 millijoules looks right.
 
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Yes, 0.288mJ looks correct.
But the energy supplied by the voltage source is 0.576mJ, and maybe that's what they printed as the model answer by mistake.
 
cnh1995 said:
Yes, 0.288mJ looks correct.
But the energy supplied by the voltage source is 0.576mJ, and maybe that's what they printed as the model answer by mistake.
cnh1995: I agree that 0.288mJ looks correct. But I have not been able to see how to support your statement that "the energy supplied by the voltage source is 0.576mJ". Assuming you are correct, is it possible to interpret the assigned calculation to mean the energy supplied by the voltage source?
 
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sojsail said:
But I have not been able to see how to support your statement that "the energy supplied by the voltage source is 0.576mJ".
Well, it can be shown mathematically, but I don't think this problem requires that. :smile:
I mentioned it because I thought perhaps the given wrong answer key had something to do with it.