Final answer:
The capacitance of a pair of circular plates with a given radius and separation can be calculated using the formula C = (ε₀ * A) / d.
Step-by-step explanation:
The capacitance of a pair of circular plates can be calculated using the formula:
C = (ε₀ * A) / d
Where C is the capacitance, ε₀ is the permittivity of free space (8.85 x 10^-12 F/m), A is the area of one plate, and d is the separation between the plates.
In this case, the radius of each circular plate is 3.0 cm, so the area of one plate is:
A = π * r²
Substituting the values into the formula:
C = (8.85 x 10^-12 F/m * π * (0.03 m)²) / (0.0023 m)
Simplifying the expression gives the capacitance:
C ≈ 2.38 x 10^-12 F