- #1
RK1992
- 89
- 0
this isn't homework, I am doing revision for an exam :)
a 180 microfarad capacitor is charged so that is has a PD of 100v across the plates. i calculate the energy stored as 0.5cv² = 0.9J
the question then asks me to calculate the work done by the battery in charging the capacitor. the mark scheme says that i should use W = QV = CV² and should therefore get 1.8J
why is the work done in charging the capacitor different to the energy stored on it? i have never heard my teacher mention this fact in lessons, so i seriously have no idea where this has come from.. where does this equation come from? thanks
a 180 microfarad capacitor is charged so that is has a PD of 100v across the plates. i calculate the energy stored as 0.5cv² = 0.9J
the question then asks me to calculate the work done by the battery in charging the capacitor. the mark scheme says that i should use W = QV = CV² and should therefore get 1.8J
why is the work done in charging the capacitor different to the energy stored on it? i have never heard my teacher mention this fact in lessons, so i seriously have no idea where this has come from.. where does this equation come from? thanks