Poynting vector

The vector cross product of the electric field E and the magnetic field H:

This vector specifies the instantaneous rate of propagation of electromagnetic energy. The amount of energy transmitted per unit time across a unit area, with normal n, is n · S. In optics, irradiance is the Poynting vector averaged over a time sufficiently long compared with the period but short when compared to the characteristic response times of radiometric instruments.

INDEX
A
B
C
D
E
F
G
H
I
J
K
L
M
N
O
P
Q
R
S
T
U
V
W
X
Y
Z
0
1
2
3
4
5
6
7
8
9