How to Calculate the Capacitance of Metal Plates
- 1). Measure the area of one plate's surface (in square meters). Because the plates should have identical shapes, you only need to measure one of them. For a list of formulas for calculating the area of common two-dimensional shapes, see the "Resources section below.
- 2). Gently slide the inside jaws of a Vernier caliper into the space between the plates and expand them to measure the distance between the plates (in millimeters). For a diagram of a Vernier caliper, see the "Resources" section below.
- 3). Divide the distance from Step 2 by 1000 to convert its units to meters.
- 4). Determine the dielectric constant for the material separating the two surfaces of the plates. For a complete listing of dielectric constants (sorted alphabetically by material), see the "Resources" section below. Note: if there is nothing between the plates (except for air), then the dielectric constant is "1".
- 5). Multiply the dielectric constant by the area of the plate (from Step 1).
- 6). Multiply this number by 8.854 x 10^-12 Farads per meter. This is a constant known as the "permittivity of space".
- 7). Divide the result from Step 6 by the distance between the plates (from Step 3). This value is the capacitance of the metal plates (in Farads or "Coulumbs/Volt").
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