Question

A parallel-plate capacitor is made from two aluminum foil sheets, each 3.6 cm long and 5.4 cm wide. The two sheets are separated by a distance of 0.028 mm.

1) What is the absolute value of the charge on the plate with the lower voltage?

qlower =

2) Now a piece of teflon with a dielectric constant of κ = 2.1 is inserted to fill the space between the plate. What is the capacitance of the capacitor with the teflon inserted?

C =

3) If a potential difference of 1 volts is applied as before across the two plates of this capacitor, what is the absolute value of the charge on the plate with the higher voltage with the teflon inserted?

qhigher =

Answer 1

The charge on the plate kept at lower potential is same as that of the charge on the plate kept at higher potential.