Q 0 = ε ′ / ε ″ =1/tan δ MathType@MTEF@5@5@+=feaagCart1ev2aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbbjxAHXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaeqabiGaciGacaqadmaadaqaaqaaaOqaaiaadgfadaWgaaWcbaGaaGimaaqabaGccqGH9aqpcuaH1oqzgaqbaiaac+cacuaH1oqzgaGbaiabg2da9iaaigdacaGGVaGaciiDaiaacggacaGGUbGaeqiTdqgaaa@431C@
Note 1 to entry: The quality factor of a material is also defined as 2π times the ratio of the stored electromagnetic energy to the energy dissipated in the material per cycle. It is frequency dependent.