Relative Permittivities and Permiabilities


MATERIAL		REL. PERMIT.	REL. PERMIAB.	BREAKDOWN(kv/inch)

Vacuum			1		1		-
Air			1.006				75
Paper			2				?
Pressboard		2				?
Cotton tape(Rubbered)	2				?
Empire cloth		2				?
Paper (oiled)		2				?
Paper (paraffined)	2.5				1300
Transformer oil		4				400
Shellac			3				?
Bakelite		6				400
Paraffin wax		3				?
Mica			5-7				5000
Porcelain		6-7				200
Ceramic			7500??				75
Glass			7-7.5				3000
Marble			8				?
Rubber			2.5				700
Teflon			2				1500
Ebonite			2.5				
Gutta-percha		4				
Polyethylene		2.3				
Xylonite		?				?
Ivoride			?				?