|MadSci Network: Physics|
Peter, yes it is possible! However, I'm not sure if the method you prescribe is practical with today's technology. Theoretically, when you pass current through a coil, an electromagnetic force is generated in a direction normal to the current. An easy way to envision this, without getting bogged down into vector geometry, etc., is to use your hand to illustrate. First, take your right hand, and make it flat on a surface like a table at home. Next, extend your thumb straight out away from your hand, like a "thumbs up". Keep your fingers together and flat, with the palm against the table. Now imagine 3 axis, x, y and z. The z axis extends up from your wrist, towards the ceiling. For this situation, as different situations may use a different illustration, rotate your hand flat against the table to angle your thumb in the direction you wish to apply your force. If you want to move away from that direction-push off-simply curl your fingers around the imaginary bar running under your thoumb and across your palm. This is what a positive or counter-clockwise current will do. If you wanted to move in the direction of your thumb, simply flip your hand over-rather than breaking your fingers to get them to curl the opposite way-and curl them as before. This is a negative or clockwise current. Noticee your thumb is pointing the opposite way, unless you've broken your fingers :) The thumb represents the resultant force, normal to the current. That being said, the hard part comes in the nature of the force. Unlike a rocket or turbine, which react directly with the simpler physical aspects of their environment, an electro-magnetic engine or thrust generator requires a similar field to interact with. In other words, in order for the rocket idea to work, you would need a nother field, generating a force normal to the rocket's field. Now, you've opened a whole new can of worms :) Most important in this situation, is your thrust. The thrust in this case results from the repulsion strength between the two fields. The closer the two fields are to being exact opposites, the more resultant thrust will effect the mass of the rocket; make it move faster. An electro-magnetic field's strength or force is reduced by a factor of 1 over the square of the increasing distance. This affects both the design of the rocket and the design of the launching platform as well. Simply put, as the distance increases between the rocket and the launching platform's field generator the velocity of the rocket will drop off dramatically in proportion to the square of the distance between the rocket and the field. Let's say you were moving at speed x at "lift off". At distance z, the rocket is now only moving at x/(z^2)-SIGNIFICANTLY SLOWER!!! To combat this effect, either the rocket and/or the launch platform generator would have to significantly ramp up the strength of their fields, consuming much much larger ammounts of energy. Therefore, although your model is possible, with today's technology and energy generation capabilities, your model is not practical. However, more simple kinetics, like firing bullets, etc...a simple modification to your model for "short range" use could prove to be worth looking into. Militaries around the world are spending more and more money into this field....so who knows...one day...when we've discovered fusion... Thanks for your question, I hope this hasn't dampened your thoughts, but given you some helpful information. Ken
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