Post Your Answer
6 months ago in Electromagnetics By Pranav
Wait, there are two different permittivities of free space?
I keep seeing "permittivity of free space" and "relative permittivity of free space" and they have different values. Which one is right?
All Answers (1 Answers In All)
By Babita Answered 2 months ago
They're not competing they're different things. ε? (about 8.854×10?¹² F/m) is an absolute physical constant. It tells you how much electric field the vacuum itself can support. Relative permittivity (ε?) is a ratio: it compares a material's permittivity to ε?. For free space, that ratio is exactly 1. So the "relative permittivity of free space" is just 1, by definition. Same vacuum, two different measurements.
Reply to Babita
Related Questions