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ELECTRICITY AND MAGNETISM

In the following, e = dielectric permittivity, p = permeability of conduc­tor, p — permeability of surrounding medium, a — conductivity, f = uj/2-n = radiation frequency, Km = p/po and Ke = e/eo- Where subscripts are used, '1' denotes a conducting medium and '2' a propagating (lossless dielectric) medium. All units are SI unless otherwise specified.

Permittivity of free space

Permeability of free space

Resistance of free space

Capacity of parallel plates of area A, separated by distance d

Capacity of concentric cylinders of length I, radii a, b

Capacity of concentric spheres of radii a, b

Self-inductance of wire of length I, carrying uniform current

Mutual inductance of parallel wires of length I, radius a, separated by distance d

Inductance of circular loop of radius 6, made of wire of radius a, carrying uniform current

Relaxation time in a lossy medium

Skin depth in a lossy medium

Wave impedance in a lossy medium

Transmission coefficient at conducting surface9 (good only for T < 1)

Field at distance r from straight wire carrying current I (amperes)

Field at distance z along axis from circular loop of radius a carrying current I

e0 = 8.8542 x 10~12 Fm

po = 4tt x 10 7 H m" = 1.2566 X 10~6 Hm

r0 = (poAo)1/2 = 376.73 C = eA/d

C =2tt el/\n(b/a)

C = 47reab/(b - a)

= pi

= (pi/4tt) [1 + 41n(d/a)]

-l

L

L

L = b j// [ln(86/a) - 2] + p/4 j

r    — e/(j

b   = (2/ujpa)1/2 = (tTfpa)~1/2

Z   ={p/(e + i*/u;)]1/2

T   = 4.22 x 10-4(/KmiKe2/cr)1/2

Bq = pl/27rr tesla

= 0.21 /r gauss (r in cm)

B2= pa2//[2(a2 + z2)3/2]

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