Capacitance Calculator

What Is Capacitance?

“It is the ability of a capacitor to store charge”

The capacitance of a capacitor is always dependent on two factors that include:

• Dielectric medium
• Distance between the capacitor plates

Parallel Plate Capacitor Formula:

Our parallel plate capacitor calculator uses the standard equation to calculate capacitance. However, if you want to perform manual calculations, use the formula:

Capacitance: \[ C = \frac{\varepsilon A}{s} \]

Where:

• \(\varepsilon = 8.854 \ \text{pF/m}\) (permittivity of free space)
• \(A\) = Area of the plates
• \(s\) = Distance between the plates

The above permittivity value is the standard that is used used by this capacitor capacitance calculator with no specific capacitance entered.

How To Find Capacitance?

Basically, capacitance is the ratio of the charge in a capacitor to the voltage across its plates. Let us figure out through an example!

Statement:

If the area occupied by the capacitor plates is about \(125 \ \text{mm}^2\) and the separation between the plates is about \(7 \ \text{mm}\), how do we calculate capacitance? (The relative permittivity of space is \(\varepsilon = 0.000124 \ \text{F/m}\).)

Solution:

Using the parallel plate capacitance formula:

\[ C = \frac{\varepsilon A}{s} \]

Convert units to meters first: \[ A = 125 \ \text{mm}^2 = 125 \times 10^{-6} \ \text{m}^2, \quad s = 7 \ \text{mm} = 0.007 \ \text{m} \]

Substitute values:

\[ C = \frac{0.000124 \times 125 \times 10^{-6}}{0.007} = \frac{0.0000155}{0.007} \approx 0.00221 \ \text{F} \]

This is the required capacitance at which the parallel plate capacitor will work normally without any trouble.

Working of Capacitance Calculator:

Our calculator requires certain values to calculate capacitance. Let’s explore these ones by one!

Input:

• Enter the values of area, permittivity, and space between plates
• Tap Calculate

Output: The capacitance of a parallel plate capacitor Conversions in other related units of measurement

Faqs:

What Is The Value of \(k\) in Capacitance?

• For free space: k = 1
• For all other media: k > 1

To accurately calculate capacitance with any value of \(k\), you may let this capacitance calculator do all the maths for you.

What Is a Normal Capacitance?

The normal capacitance value typically ranges from 1 nF to 1 µF.

What Causes Capacitance To Increase?

The increasing area of the plate is directly proportional to the capacitance. So to get more capacitance value, you need to use a capacitor with a high capacitance value.

What Causes Negative Capacitance?

When the change introduced in charge changes the voltage value but in the opposite direction, the capacitance will be considered negative.

Capacitance Conversion Chart:

References:

From the source Wikipedia: Capacitance, Self-capacitance, Mutual capacitance, Capacitance matrix, Stray capacitance, Capacitance of conductors with simple shapes, Energy storage From the source Khan Academy: Capacitors and capacitance