Based on the second law of thermodynamics why must a machine always be less than 100% efficient?

Physics

1 answer:

AleksandrR [38]3 years ago

4 0

Answer: B.Heat is never converted completely into mechanical energy.

Explanation:

According to the second principle of thermodynamics:

<em>"The amount of entropy in the universe tends to increase over time" </em>

However the first formulation of this law (by Sadi Carnot) states:

<em>"There is an upper limit to the efficiency of conversion of heat to work, in a heat engine "</em>

This means the heat cannot be completely transformed into mechanical energy in a machine. That is why a machine's effieciency is always less than 100%

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