A Capacitor Paradox
نویسندگان
چکیده
Two capacitors of equal capacitance C are connected in parallel by wires of negligible resistance and a switch, as shown in the lefthand figure below. Initially the switch is open, one capacitor is charged to voltage V0, and charge Q0 = CV0, while the other is uncharged. At time t = 0 the switch is closed. If there were no damping (dissipative) mechanism, the circuit would then oscillate forever, at a frequency dependent on the self inductance L and the capacitance C , namely f = ω/2π = 1/2π √ 2LC . However, even in a circuit with zero Ohmic resistance, damping occurs due to the radiation of the oscillating charges, and eventually a static charge distribution results, with charge Qi/2 and voltage Vi/2, on each capacitor.
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تاریخ انتشار 2002