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Q & A: Self-powered motor

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Most recent answer: 07/12/2015
Q:
If you mix Mercury with Gold, does it become more conductive but yet not become magnetic? The idea is if you had a good conductive liquid metal and an efficient pump, could you push the conductive liquid through copper coils around a magnet to generate electricity. If the pump was efficient enough (or power generated great enough) you could self power the pump yet use the extra to power things like a light bulb (sorta like a transmitter takes a small amount of what it lets through). Yes, I could be a billionaire or more if that worked, I'd rater just see it happen (and cost kept low).
- David (age 45)
Las Vegas, NV
A:

I should admit that I did not fully understand the working principle of your system. But whatever you do, the overall system (blackbox) should obey the laws of physics, one of which says a reaction will not spontaneously happen without increasing the entropy of the universe. Suppose such a power plant exists. Then we could use it to power a refrigerator, which takes up heat from a low temperature reservoir and deposits into a warmer one. Increasing entropy means making everything as randomly distributed as possible, i.e. reducing the temperature gradients. This is completely opposite of what (your generator + my refrigerator) are doing without any energy input, so such a system cannot exist.

Tunc

 

As Tunc wrote, this can't work. It does one of two things:

1. Create energy. That violates energy conservation, called the first law of thermodynamics.

2. Suck heat from the environment, reducing its entropy, violating what's called the second law of thermodynamics, as described by Tunc.

Imaginary devices like this are called perpetual motion machines. No real ones can exist.   Mike W.


(published on 07/12/2015)

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