A physicist is designing two different parallel-plate capacitors for a tuning circuit.
The first capacitor has circular plates of radius r r\,r separated by a distance 2d2d2d, and the gap between the plates is completely filled with a ceramic dielectric of relative permittivity ϵr\epsilon_rϵr.
The second capacitor has circular plates of radius 3r 3r\,3r separated by a distance ddd, and the gap is completely filled with a liquid dielectric of relative permittivity 2.0.
Both capacitors have the same capacitance. What is the relative permittivity ϵr \epsilon_r\,ϵr of the ceramic dielectric in the first capacitor?
9.09.09.0
121212
181818
363636
