Retarded field bench

Nothing in a field travels faster than c

t 0.00 s — fps field —

Probe
Total E
Radiated part
Bz

Energy flux

P radiated
line integral
peak lobe

Time-averaged. The polar plot is outward flux against angle; the dashed circle is zero.

Probes

Two probes at different distances let you measure c from the delay between them.

source
path difference
measured delay
c from delay

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