I've been thinking while studying physics and came up with the following problem: A current I, starting at a point A, flows through a resistor with R=25 kΩ, a capacitor with C=4milliF, and an inductor with L=7 Henry to finish in point B. At a time when Q=8 milliC and the current I=0.2 milliAmps and is changing at a rate dI/dt=-1.0 A/s, what is the potential difference VB-VA (inVolts)? Solution: Moving in the direction of the current flow we have VB-VA=-IR-Q/C-L dI/dt IR =5 V Q/C = 2 V L dI/dt = -7 V Thus, VB-VA = -5V -2V +7V = 0V (???) how is this possible? There must be some loss due to the resistor, otherwise we could be able to make perfect circuits with no losses due to household devices for example.