Why the potential energy of a spherical conductor is U= (1/2)VQ and why not U=VQ ?

Why the potential energy of a spherical conductor is         U= (1/2)VQ and why not  U=VQ ?


2 Answers

879 Points
12 years ago

Dear pavan,

Energy stored in capacitor is E=QV/2 or E=CV2/2 or E=Q2/2C
factor 1/2 is due to average potential difference across the capacitor while it is charged.
• Battery supply QV amount of energy during charging a capacitor but energy stored in capacitor is QV/2 ,
the another half of energy is transferred into the circuit resistance in the form of heat. Thus, heat in the wire=energy supplied by battery-energy stored in the capacitor =QV-QV/2 = QV/2.


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Askiitians Expert

Sagar Singh

B.Tech, IIT Delhi

vikas askiitian expert
509 Points
12 years ago

energy stored in a capacitor=CV2/2

  V is the potential of sphere...


so energy=QV/2

energy stored is potential energy of sphere so PE=VQ/2  not  VQ

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