Why can’t perpetual motion provide an infinite energy source?
In: Physics
It’s not so much that there is a specific reason why we can’t get infinite energy out of a perpetual motion machine. It’s because simply one of the apparent rules of the universe says we can’t.
Through thorough testing, one consistent rule of the universe is that energy can not be created or destroyed. Any time it seemed as if we could get infinite energy, it turned out that energy was coming from somewhere we didn’t realize. Every time we thought energy was being lost from a system, there was an exit point for the energy we didn’t account for. This is why all perpetual motion machines fail to produce energy. Reality simply isn’t set up that way.
A perpetual motion machine (PMM) requires MORE energy then what you started with because some energy will always be lost as heat. Where does the PMM get this EXTRA energy from?
It would be like dropping a weight onto a trampoline and the weight bouncing higher and higher with each bounce. Or like a smaller battery being able to fully charge a larger battery.
This is really a basic law of the universe: you can’t get out more energy than you put in. (Accounting for the fact mass and energy are convertible.)
Starting from this basic principle you can start to look at the problems with specific perpetual motion machines, which are all basically the same – either you’re taking more energy out of the system than you put in, or you’re losing some energy due to inefficiency (almost always heat). Both either lead to the system slowing down or you having to put more energy in than you take out.
There is ALWAYS energy lost as heat in any reaction. Because of this, perpetual motion is impossible because you will always be losing energy. In order for any process to continue, there must be an input of energy.
Let’s start with perpetual motion on Earth doesn’t exist because it would require an infinite energy source.
Now, let’s say you have something already in motion in the vacuum of space so it’s not going to slow itself down ( and no friction, just a body moving in space ). The moment you get this to perform work, to create useable energy, you’ll end up slowing it down.
If the machine is full of energy and working without ever stopping (which is still not possible due to other things, but let’s pretend it is) once you connect it to something to harvest the energy you will slow it down. Therefore, it cannot continue forever. The examples of what we see as perpetual machines are either very efficient toys that seem to run a very long time or hoaxes with fake energy added like a hidden battery motor.
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