Which one of the following statements is correct?a)A machine that vio...
First Law of Thermodynamics: - Energy can neither be destroyed nor created when it disappears in one form; it must re-appear at the same time in other forms.
- When a closed system executes a complete cycle, the sum of heat interactions is equal to the sum of work interactions.
Second Law of Thermodynamics:
It has two statements:
- Kelvin-Planck Statement: It is impossible to devise a cyclically operating device, the sole effect of which is to absorb energy in the form of heat from a single thermal reservoir and to deliver an equivalent amount of work
- Clausius Statement: It is impossible to devise a cyclically operating device, the sole effect of which is to transfer energy in the form of heat from a low-temperature body to a high-temperature body
Violation of the Kelvin statement implies a violation of the Clausius statement, i.e., the Clausius statement implies the Kelvin statement.
Similarly, the Kelvin statement implies the Clausius statement, and hence the two are equivalent.
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Which one of the following statements is correct?a)A machine that vio...
Explanation:
The first law of thermodynamics, also known as the law of conservation of energy, states that energy cannot be created or destroyed, only transferred or converted from one form to another. This law is fundamental in understanding the behavior of machines and systems in thermodynamics.
Statement a: A machine that violates Clausius statement will violate the first law of thermodynamics.
The Clausius statement is a formulation of the second law of thermodynamics, which states that heat cannot spontaneously flow from a colder body to a hotter body. Violating this statement would mean that heat is flowing from a colder body to a hotter body without any external work input. However, this violation does not necessarily violate the first law of thermodynamics, as energy can still be conserved even if heat flows in such a way.
Statement b: A machine that violates the Kelvin-Plank statement will violate the first law of thermodynamics.
The Kelvin-Plank statement is another formulation of the second law of thermodynamics, which states that no machine can operate in a cycle and produce no effect other than the extraction of heat from a reservoir and the performance of an equivalent amount of work. Violating this statement would mean that a machine is able to produce more work output than the amount of heat it receives, which directly contradicts the first law of thermodynamics. Therefore, if the Kelvin-Plank statement is violated, the first law of thermodynamics is also violated.
Statement c: A machine that violates the second law of thermodynamics will violate the first law of thermodynamics.
The second law of thermodynamics encompasses various statements, including the Clausius and Kelvin-Plank statements. Violating any of these statements would mean that the machine is operating in a way that is not consistent with the principles of thermodynamics. However, this violation does not directly violate the first law of thermodynamics, as energy conservation can still be maintained. Therefore, statement c is incorrect.
Statement d: A machine that violates the Kelvin-Plank statement will violate the Clausius statement.
The Kelvin-Plank statement and the Clausius statement are both formulations of the second law of thermodynamics, but they focus on different aspects. The Kelvin-Plank statement relates to the impossibility of a machine operating in a cycle and producing no other effect than extracting heat from a reservoir and performing an equivalent amount of work. The Clausius statement relates to the impossibility of heat spontaneously flowing from a colder body to a hotter body. Violating the Kelvin-Plank statement implies that a machine can operate in a cycle and produce more work output than the amount of heat it receives, which also violates the Clausius statement. Therefore, statement d is correct.