Propelling a Rod in Space with an Electric Motor

AI Thread Summary
The discussion centers on the feasibility of using a large electric motor to propel a rod in space, highlighting challenges such as the inefficiency of rocket fuel production compared to the power generated. It emphasizes that while a vacuum eliminates air friction and gravity, it does not provide a propulsion mechanism, as there is no wind to utilize. The initial acceleration would require a rocket, but the ongoing energy generation from a megawatt-scale generator is questioned. Superconducting materials can reduce resistance but do not negate the electromagnetic forces that oppose motor rotation. Ultimately, the concept faces significant practical limitations, reinforcing the idea that there are no effortless solutions in this scenario.
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Here is the situation. A large electric motor has a long rod attached at a 90º to the motor shaft and is accelerated at the end of the rod by something (rocket, fan, etc) and is in space (a vacuum). Thoughts?
 
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The production of the fuel for rocket would out-weigh the power created by the generator. There's no wind in space to push a fan. I think that the fact that it's in a vacuum only buys you freedom from the friction of "air" and gravity on the system.
 
The rocket would just be to get it started, to accelerate it to a high speed. I'm talking about an extremely large generator producing megawatts. The temperature in space is in the low kelvins, let's say 40k or less in the areas where we would be using this device, like in a deep crater on the moon that never receives sunlight. Using superconducting materials will eliminate resistance.
 
Using superconducting materials does not eliminate the electromagnetic forces that oppose the rotation of the motor. That's not resistance. There is no free lunch.
 

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