Answer:
C = 3.77*10⁻¹⁰ F = 377 pF
Q = 1.13*10⁻⁵ C
Explanation:
Given
D = 8.0 cm = 0.08 m
d = 0.95 cm = 0.95*10⁻² m
k = 80.4 (dielectric constant of the milk)
V = 30000 V
C = ?
Q = ?
We can get the capacitance of the system applying the formula
C = k*ε₀*A / d
where
ε₀ = 8.854*10⁻¹² F/m
and A = π*D²/4 = π*(0.08 m)²/4
⇒ A = 0.00502655 m²
then
C = (80.4)*(8.854*10⁻¹² F/m)*(0.00502655 m²) / (0.95*10⁻² m)
⇒ C = 3.77*10⁻¹⁰ F = 377 pF
Now, we use the following equation in order to obtain the charge on each plate when they are fully charged
Q = C*V
⇒ Q = (3.77*10⁻¹⁰ F)*(30000 V)
⇒ Q = 1.13*10⁻⁵ C