Propelling in a Vacuum
Name: Ed B.
Is there any way of propelling something through a vacuum
(or near vacuum) using electricity rather than matter.
Electricity is mater in motion - electrons. There has been some work done on
electrical propulsion. I do not know what the current state of the
but it works on Newton's third law of motion... action and
are accelerated from a negative plate toward a positively charged grid. The
electrons not captured by the positive grid and being expelled are the source
of the acceleration for the vehicle.
To start moving forward, you must gain momentum in that direction. For this
to happen, something else must gain just as much momentum in the reverse
direction. If you can push something else backward with electricity, then
that thing will also push you forward. You cannot be pushed forward without
something to push back against. The best you could do in a vacuum with
electricity is emit light in the backward direction. By "pushing back" on
the light, the light could push forward on you. Light does have a tiny bit
of momentum. The amount of light you would have to emit, however, would be
enormous just to receive a tiny shove. It would not be a reasonable
Dr. Ken Mellendorf
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Update: June 2012