Capacitance equired to store an energy of

AI Thread Summary
To determine the capacitance required to store 8 kWh at a potential difference of 600 V, the energy must first be converted to joules, resulting in 28,800,000 J. The formula U = 1/2 CV^2 is used to relate energy (U) to capacitance (C) and voltage (V). After substituting the values into the formula, the correct capacitance can be calculated. The initial calculations were incorrect due to not properly converting kilowatt-hours to joules. The final capacitance value is confirmed to be accurate after addressing the conversion error.
mr_coffee
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Hello everyone. The question is:
What capacitance is required to store an energy of 8 kWh at a potential difference of 600 V?
\This seems like a simple problem..our professor hasn't went over this yet but i saw in the book. P = U/t; I also saw; U = 1/2CV^2; So they gave me U right? because P = U/t, so U = 8 kWh, i converted this into 8kWsecond, by doing this:
8kwh x 3600sec = 28800kws; I then used:
C = (2U)/v^2; C = [2*28800]/(600)^2 = .16 which was wrong, i also tried just using 8, and 8/3600, all didn't work.
 
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1 KWH = 1*1000*3600 J = 3.6 x 10^6 J (S.I. Unit of energy)
 
mr_coffee said:
8kwh x 3600sec = 28800kws;

There is still the KILO in there, which you should convert numerically (hint: 1000:-)
 
Ahhh thank you guys, worked great :)
 
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