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Comment: Re:This again? (Score 1) 473

by Whiteox (#49597467) Attached to: New Test Supports NASA's Controversial EM Drive

I agree. Some advanced high school physics can explain more.
There is a 3rd option here. That is of force vectors. e.g. repulsion between a number of fixed coils @ 45 degrees to each other in the shape of a cone, causes a magnetic field. The simple vector calculation would show that the field is pushed outward, away from the coils like the shape of a rocket exhaust.
What if you replace the coils with a cone* of electrons? As the repulsive force between parallel streams of electrons is enormous yet shaped as a cone, the repulsive force pushes the electrons away from the center of the cone, outside the cone itself. Again, it is easy to visualize the vectors here. A CRT only uses a single stream of electrons. Add another stream and the resultant force between them will push them away from each other. Nothing remarkable here.
But what if you contain the electrons with an external magnetic field, pushing the repulsive force back toward the center?
You will have force acting on nothing. No law was broken. The electrons are contained, moving from the apex of the cone to its base. The repulsive force is directed out of the base. There are no particles emitted, just force.

There's no magic in this. If you think about it, this force vector engine can have quite a few applications.

*The cone is actually a funnel within a funnel, sealed at the apex and base. The electron streams are in a vacuum between the walls of the funnels, moving from apex to base.

We cannot command nature except by obeying her. -- Sir Francis Bacon