Diagram illustrating generation of electromagnetic field
by an electric charge
: a static charge (grey small circle at the centre) generates electrostatic field
(blue area) which statically extends away into space. A sudden acceleration of the charge (dark blue small circle) creates an electromagnetic pulse (red ring) which radiates
away into space at the speed of light
, and the space far away still contains the electrostatic field from the time when the charge was stationary (as indicated by grey lines). A charge moving at a constant velocity v
generates electric and magnetic field attached with the charge (green area). The field lines
(black lines) show the direction and intensity of electric field.