A capacitor is hooked up to a resistor and an AC voltage source as shown in the figure. The output of the source is given by V(t) = V0 sin ωt. The plates of the capacitor are disks of radius R. Point P is directly between the two plates, equidistant from them and a distance R/2 from the center axis. At point P
A) there is no magnetic field because there is no charge moving between the plates.
B) there is a constant magnetic field.
C) there is a time-varying magnetic field.

Question

A capacitor is hooked up to a resistor and an AC voltage source as shown in the figure. The output of the source is given by V(t) = V0 sin ωt. The plates of the capacitor are disks of radius R. Point P is directly between the two plates, equidistant from them and a distance R/2 from the center axis. At point P 
A) there is no magnetic field because there is no charge moving between the plates. 
B) there is a constant magnetic field. 
C) there is a time-varying magnetic field.

Quizplus · Accepted Answer

As the AC voltage source creates a changing electric field in the capacitor, the charges on the plates of the capacitor will be alternately attracted and repelled. This movement of charges creates a time-varying current in the circuit, which in turn creates a time-varying magnetic field around the connecting wire. Therefore, at point P, there will be a time-varying magnetic field.

A Capacitor Is Hooked Up to a Resistor and an AC