17. Permittivities
(relative values)
Dielectric
a
Dielectric
a
Water
81
Mica
7.5
Air
1.00058
Alcohol
26
Kerosene
2.0
Glass
6.0
Paraffin
2.0
Porcelain
6.0
Plexiglas
3.5
Ebonite
2.7
Polyethylene
2.3
18. Resistivities of Conductors
Conductor
Resistivity (at 20 °C)
p, nid•m
Temperature coefficient
a, kK-1
Aluminium
25
4.5
Tungsten
50
4.8
Iron
90
6.5
Gold
20
4.0
Copper
16
4.3
Lead
190
4.2
Silver
15
4.1
19. Magnetic Susceptibilities of Para- and Diamagnetics
Paramagnetic substance
u.-1, 10-6
Diamagnetic substance
p.-1, 10-6
Nitrogen
0.013
Hydrogen
—0.063
Air
0.38
Benzene
—7.5
Oxygen
1.9
Water
—9.0
Ebonite
14
Copper
—10.3
Aluminium
23
Glass
—12.6
Tungsten
176
Rock-salt
—12.6
Platinum
360
Quartz
—15.1
Liquid oxygen
3400
Bismuth
—176
25-9451