a perpetual motion machine is a machine that, when set in motion, will never come to a halt. why is such a machine not possible?
A perpetual motion machine is a hypothetical machine that can operate indefinitely without an external source of energy. These machines violate the fundamental laws of thermodynamics, specifically the first and second laws.
The first law of thermodynamics, also known as the law of energy conservation, states that energy cannot be created or destroyed; it can only be transferred or transformed from one form to another. This means that a perpetual motion machine cannot create energy out of nothing. It would require an infinite supply of energy to keep running, which is not possible.
The second law of thermodynamics states that the entropy (a measure of disorder or randomness) of an isolated system always increases. In other words, energy tends to spread out and become less usable over time. This law implies that no machine can have 100% efficiency, meaning that there will always be some energy losses in the form of heat, friction, or other inefficiencies. These losses would eventually bring any perpetual motion machine to a halt.
In summary, a perpetual motion machine is not possible because it would violate the fundamental laws of thermodynamics by creating energy out of nothing and having 100% efficiency.