Question:
A parallel-plate capacitor has a plate area of 0.02 m² and a separation distance between the plates of 0.005 m. The space between the plates is filled with a dielectric material with a dielectric constant of 4. Determine the capacitance of the capacitor.
Answer:
The capacitance of a parallel-plate capacitor is given by the formula:
C=dε0⋅εr⋅Awhere:
- C is the capacitance of the capacitor
- ε0 is the permittivity of free space, approximately 8.85×10−12F/m
- εr is the relative permittivity (dielectric constant) of the material between the plates
- A is the area of each plate
- d is the separation distance between the plates
Plugging in the given values:
A=0.02m² \
d=0.005m \
εr=4
The permittivity of free space ε0 is a fundamental constant and does not change.
Substituting these values into the formula:
C=0.005m(8.85×10−12F/m)⋅(4)⋅(0.02m²)Calculating the expression:
C=0.005m8.85×10−12F/m⋅4⋅0.02m²C=0.005m(8.85×4)×10−12+0+2FC=0.005m35.4×10−10FC=7.08μFTherefore, the capacitance of the parallel-plate capacitor is 7.08 microfarads.