Calculating Capacitance for a Water-Filled Parallel-Plate Capacitor"

[pat666]

Homework Statement

The capacitance of a water-filled parallel-plate capacitor with plate area 3.0×10^−3m^2 and separation 4.0×10^−2 mm is
0.66 uF
1.3 nF
53 nF
660 nF

Homework Equations

C=E_0A/d

The Attempt at a Solution

C=8.85*10^-12*3*10^-3/4*10^-5
C=6.64*10^-10
This is none of the options. I think that the constant 8.85*10^-12 may be wrong since the capacitor is water not air?

 

[rl.bhat]

Homework Statement

The capacitance of a water-filled parallel-plate capacitor with plate area 3.0×10^−3m^2 and separation 4.0×10^−2 mm is
0.66 uF
1.3 nF
53 nF
660 nF

Homework Equations

C=E_0A/d

The Attempt at a Solution

C=8.85*10^-12*3*10^-3/4*10^-5
C=6.64*10^-10
This is none of the options. I think that the constant 8.85*10^-12 may be wrong since the capacitor is water not air?

C = KεοA/d where K is the dielectric constant of water. Find its value in Wikipedia. Answer is 53 nF.

 

[pat666]

thanks a lot for that.