Is it possible to build a perpetual motion machine?
no, it would be a violation of Newtons third law...it would have to generate more energy than the energy it uses
For every action, there is an equal and opposite reaction.
I think it is. I think about satellites. The definition of a pmm is once you start it you don´t need any extra power to keep it going. Satellites don´t get any extra power after they have been launched. gravity does the rest of the work for eternity as long as no meteorite crashes intothe satellite.
A time can come when you will be able to design a machine which can go on working for ever without the expenditure of energy is it possible?
If you are suggesting a "perpetual motion" scenerio, it would violate the first or second laws of thermodynamics. Many inventors dream of perpetual motion machines, but they are an impossible dream according to the laws of thermodynamics. The second law of thermodynamics says that an engine or process of any type must always have an efficiency of less than 100%. A perpetual motion machine that uses a generator to power the motor that runs the…
you can't build time travel. Though in the law of Physics, it is possible to build a time machine, however that is almost to impossible, but remember when people though that the world was flat? they were wrong, the world is round. So you might be saying 'time machine' may not be possible, but maybe in future someone can create one.
The term "gravity generator" seems to be used for different concepts. The first hits in Google are related to machines that purport to provide "free energy", in other words, a perpetuum mobile (perpetual motion machine). Such machines are not possible to build - there are good reasons to believe that the Law of Conservation of Energy is valid, in other words, you can't make energy out of nothing. You can see many such designs, and…
How do you build an electric motor run a generator to power itself if the motor has a larger gear and the generator has a smaller gear?
You cannot build a motor generator set that would power itself. That would constitute a perpetual motion machine which, due to losses in various components, is impossible. Even though you spin the generator faster than the motor, the motor will be required to provide more torque, representing more power than the generator is capaple of producing.