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Name:  Ed B.
Status:  student
Age:  15
Location: N/A
Country: N/A
Date: 2000-2001


Question:
Is there any way of propelling something through a vacuum (or near vacuum) using electricity rather than matter.


Replies:
Ed -

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 research is, but it works on Newton's third law of motion... action and reaction. Electrons 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.

Larry Krengel


Ed,

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 arrangement.

Dr. Ken Mellendorf



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