Question
Hi, In cramster's response to this problem, it seem like they areusing a different equation for inital system energy than finalsystem energy---it looks like potential is squared forthe inital system energy but not the final. Is there areason for this or is it an error? Thanks!! Hi, In cramster's response to this problem, it seem like they areusing a different equation for inital system energy than finalsystem energy---it looks like potential is squared forthe inital system energy but not the final. Is there areason for this or is it an error? Thanks!!
Explanation / Answer
Given : In this solution The final energy of the system U = 1/2 QVc Where Q is charge on thecapacitor Vc is the potentaildifference The initial energy of the system U = 1/2 CV2 , This is the another form of energy stored ina capacitor. [ Capacitance = charge / potentialdifference C = Q / V ] When you are using both Capacitance and potentialdifference , to find energy of a capacitor you should use U = 1/2 C V2 So, this is correct method [ Capacitance = charge / potentialdifference C = Q / V ] When you are using both Capacitance and potentialdifference , to find energy of a capacitor you should use U = 1/2 C V2 So, this is correct method