🌐 Electric Field — E at a point, and the force on a charge placed there

The brown arrow is the FIELD E, set only by the source Q. The teal arrow is the FORCE on the test charge — flip its sign and only the teal arrow reverses.

Walkthrough 1 / 4

Step 1 — one source charge Q. It conditions the space around it; nothing else is here yet.

Source charge Q +4.0 µC

Test charge q₀ +1.0 µC

Distance r 0.40 m

Orbit rate 0.30

E = 2.2×10⁵ N/C · r = 0.40 m
F = 0.22 N · along E

E depends on Q and r only
F = q₀E — reverse q₀ and F reverses, E does not

Animation speed 1.0×