Question

Which of the following will increase the capacitance of a parallel-plate capacitor?

Check all that apply.

	Increasing the area of the plates will increase the capacitance of a parallel-plate capacitor.
	Decreasing the area of the plates will increase the capacitance of a parallel-plate capacitor.
	Decreasing the separation between the plates will increase the capacitance of a parallel-plate capacitor.
	Increasing the separation between the plates will increase the capacitance of a parallel-plate capacitor.

Answer 1

Concepts and reason

The concept of capacitance of parallel plate capacitor is required to solve the problem.

First, use the expression of capacitance of parallel plate capacitor and check for the incorrect statements. Finally, determine the correct statements by using the dependence of capacitance on area of the plates and distance between the plates.

Fundamentals

The capacitance of a parallel plate capacitor is given by the following relation:

$C = \frac{{{\varepsilon _0}A}}{d}$

Here, A is the area of the plates of the capacitor, d is the distance between the plates, ${\varepsilon _0}$ is the permittivity of free space.

The capacitance of a parallel plate capacitor is given as,

$C = \frac{{{\varepsilon _0}A}}{d}$

Here, A is the area of the plates, d is the distance between the plates, ${\varepsilon _0}$ is the permittivity of free space.

The capacitance of a parallel plate capacitor is directly proportional to the area of the capacitor. Therefore, decreasing the area of the plates will decrease the capacitance of a parallel plate capacitor.

The capacitance of a parallel plate capacitor is inversely proportional to the separation between the plates. Therefore, increasing the separation between the plates will decrease the capacitance of a parallel plate capacitor.

Hence, the statements, decreasing the area of the plates will increase the capacitance of a parallel-plate capacitor and increasing the separation between the plates will increase the capacitance of a parallel-plate capacitor are incorrect.

The capacitance of a parallel plate capacitor is given as,

$C = \frac{{{\varepsilon _0}A}}{d}$

Here, A is the area of the plates, d is the distance between the plates, ${\varepsilon _0}$ is the permittivity of free space.

The capacitance of a parallel plate capacitor is directly proportional to the area of the capacitor. Therefore, increasing the area of the plates will increase the capacitance of a parallel plate capacitor.

Hence, the statement that increasing the area of the plates will increase the capacitance of a parallel-plate capacitor is correct.

The capacitance of a parallel plate capacitor is given as,

$C = \frac{{{\varepsilon _0}A}}{d}$

Here, A is the area of the plates, d is the distance between the plates, ${\varepsilon _0}$ is the permittivity of free space.

The capacitance of a parallel plate capacitor is inversely proportional to the separation between the plates. Therefore, decreasing the separation between the plates will increase the capacitance of a parallel plate capacitor.

Hence, the statement that decreasing the separation between the plates will increase the capacitance of a parallel-plate capacitor is correct.

Ans:

Increasing the area of the plates will increase the capacitance of a parallel-plate capacitor.