Final answer:
In the real world, ideal machines do not have an efficiency of 100 percent. Efficiency in real machines is always less than 100 percent due to factors like friction and air resistance. Carnot engines, though ideal engines, cannot achieve the maximum theoretical efficiency.
Step-by-step explanation:
In the real world, ideal machines do not have an efficiency of 100 percent. Efficiency in real machines is always less than 100 percent because some work is converted into unavailable heat due to factors like friction and air resistance. The efficiency of machines is usually calculated as the ratio of useful output work to the input work. While Carnot engines are considered to be ideal engines, no engine can achieve the maximum theoretical efficiency outlined by Carnot due to dissipative processes like friction.
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