Which best describes the second law of thermodynamics? energy is not created nor destroyed, but it can change into matter. energy is not created nor destroyed, but it can change from one energy form to another. energy can be created from matter or used to produce matter. some useful energy is lost as heat whenever an energy transfer occurs. energy transfers are always 100% efficient in changing energy from one useful form to another?

The option which best describes the second law of thermodynamics is: D. some useful energy is lost as heat whenever an energy transfer occurs.

The first law of thermodynamics states that energy cannot be created nor destroyed but it can only be transformed from one form to another such as:

The second law of thermodynamics is mainly a consequence of the first law of thermodynamics.

Basically, the second law of thermodynamics deals with a physical quantity known as entropy.

Entropy refer to the tendency of a physical substance to achieve maximum disorder i.e. randomly distribute in a system.  Thus, entropy is a thermodynamic quantity that is typically used to measure the degree of maximum order or randomness of a system.

According to the second law of thermodynamics, some useful energy is lost as heat whenever there is a transformation (change) of energy from one form to another.

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Some useful energy is lost as heat whenever an energy transfer occurs.

Explanation:

When heat is converted into useful work then in that case some of the energy is transferred from high temperature reservoir to low temperature reservoir this energy transfer is always counted as heat loss.

So here we can say that

here we can say that heat is transferred from high temperature reservoir to some useful work with some of the energy is transferred to low temperature reservoir.

So efficiency of any heat engine is not possible to have 100%

so here correct answer will be

some useful energy is lost as heat whenever an energy transfer occurs.

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