Things You'll Need:
- Calculator
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Step 1
Define the dielectric constant mathematically. The dielectric constant is the ratio of the static permittivity of the test material to the static permittivity of vacuum. This may be expressed as er = es/e0 where er is the dielectric constant, es is the static permittivity of the test material and e0 is the static permittivity of vacuum. Note that the static permittivity of vacuum is therefore 1 by definition.
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Step 2
Observe the units for the dielectric constant. The dielectric constant is a number without units because it is the ratio of two quantities with the same units of measure.
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Step 3
Measure the capacitance of a test capacitor with a vacuum between its plates and call this value C0. Now measure capacitance of the same capacitor with the test material between its plates and call this value Cx.
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Step 4
Calculate the dielectric constant from the results in Step 3 such that Cx/Co. In conditions where the electromagnetic field changes over time, this value depends on the frequency of the change and is more often referred to as the relative permittivity.
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Step 5
Calculate the dielectric constant from its static electric susceptibility. This can be given as er = 1 + Xe where Xe is the static electric susceptibility of the test material.
