Static Electricity Giving Rise to Magnetism
I was wondering if "static electricity" produces
magnetism? I personally do not think it does because only a moving
electric current can cause a magnetic effect.
You are correct.
Richard Barrans Jr., Ph.D., M.Ed.
Department of Physics and Astronomy
University of Wyoming
Jake- That is exactly right,
while the static charge and high electric fields are not moving,
they make no magnetic field.
Of course, when the static charge discharges in a spark,
the magnetic field circling around the spark at that moment can be fairly intense.
I think I have heard that a spark from a human-body charged to 10kv
has a peak current between 10 and 100 picoamps,
and it all passes down a spark channel well under 1mm wide.
And if a static-charged ping-pong ball is swung in circles
(dangling on an insulating string),
it does make some very weak magnetic field,
because then it is moving.
You are correct, only a moving electric current creates a magnetic field.
Some people call the spark they get on a dry day "static electricity"
That spark is the flow of current between two voltage potential differences
(like your finger and a door knob)
So that current will generate a magnetic field.
A static electric field itself will not generate a magnetic field until a
current flows to neutralizes the charges at the ends of the electric field.
Keep curious Jake.
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Update: June 2012