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Question
What is relative permittivity?
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Solution
- Relative permittivity or dielectric constant is the ratio of the absolute permittivity of a medium to the permittivity of free space. It is denoted as K or εr.
i.e., K or εr = `ε/(ε_0)` - It is the ratio of the force between two point charges placed a certain distance apart in free space or vacuum to the force between the same two-point charges when placed at the same distance in the given medium.
i.e., K or εr = `"F"_"vacuum"/"F"_"medium"` - It is also called a specific inductive capacity or dielectric constant.
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