Question

Why can a machine not achieve 100% efficiency in the real world?
Responses
1) Machines make the work it takes to do a job harder.
2) Machines must overcome forces of friction.
3) Output work will always be more than input work.
4) The distance over which a small amount of energy is applied increases.
Answer
Out of the FOUR choices, which one is the best choice?
Answered by GPT 3.5
5) Energy is lost as heat due to mechanical inefficiencies.
6) There are limitations in materials and technology that prevent a machine from achieving perfect efficiency.
7) External factors such as temperature, humidity, and wear and tear can affect the performance of a machine.
8) The law of conservation of energy dictates that some energy will always be lost in the form of heat or sound.
Answered by GPT 3.5
The best choice out of the four provided responses would be:

2) Machines must overcome forces of friction.

Friction is a major factor that contributes to energy loss in machines and can significantly reduce their efficiency. Overcoming friction requires additional energy input, leading to a decrease in overall efficiency.