Why is it impossible to build a machine that produces more energy than it uses?
Because there is no such thing as perpetual motion. Another way to say it is that the effeciency would need to be greater than 100% and that can't be.
Efficiency can never reach 100% because there's always loss of energy during the process of carrying out work. One example is energy loss because they're converted into heat while operating.
The idea of building a machine that produces more energy than it uses is often referred to as "perpetual motion," which means a process that continues indefinitely without the need for an energy input. According to the laws of thermodynamics, specifically the first and second laws, it is impossible to create a machine that produces more energy than it consumes.
The first law of thermodynamics, also known as the law of conservation of energy, states that energy cannot be created or destroyed, only transformed from one form to another. In other words, the total amount of energy in a system remains constant. Therefore, any energy produced by a machine must come from an external source, such as electricity or fuel.
The second law of thermodynamics, known as the law of entropy, deals with the quality of energy and its tendency to disperse or degrade over time. It states that in any energy transformation process, the total entropy of a closed system will always increase. Entropy can be thought of as a measure of the randomness or disorder in a system.
When a machine converts energy from one form to another, there are unavoidable losses due to factors such as friction, heat, electrical resistance, or sound. These losses contribute to an increase in entropy and a decrease in the overall efficiency of the machine. In practical terms, this means that the energy output of a machine will always be less than the energy input, and there will be no excess energy produced.
While scientists and engineers continuously strive to improve the efficiency of energy conversion technologies, they are bound by these fundamental laws of thermodynamics, making it impossible to build a machine that produces more energy than it consumes.