I was not sure just where to ask this question, but I was wondering if the sealed bottle garden be really called a perpetual motion machine.
It has its own isolated ecosystem, and can be self sufficient for years with only needing to water once.
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Sign up to join this communityI was not sure just where to ask this question, but I was wondering if the sealed bottle garden be really called a perpetual motion machine.
It has its own isolated ecosystem, and can be self sufficient for years with only needing to water once.
There are no perpetual motion machines.
So when you think you've found one, you need to ask a couple of questions, because there will always be an answer to at least one of them.
In this case, additional energy is coming from the light that enters the sealed bottle garden. If there's no light, there's no growth.
I think this is off topic - its physics; basic thermodynamics, to be precise. But EnergyNumbers is correct. Whenever there is a claim to perpetual motion, always take as close look at the total energy inventory, including infra-red, heat, light, UV, chemical, and radioactivity. Invariably, someone has either overlooked a component of the energy balance, or is not looking at a realistic time scale.