NEET Physics: Thermal equilibrium Practice Questions
15 free multiple-choice questions on Thermal equilibrium (Thermodynamics) for NEET Physics, each with the correct answer and a step-by-step explanation. Attempt a question, then reveal the solution to check your reasoning.
Practice thousands more NEET questions in the app →Q1. In a system at thermal equilibrium, the net rate of heat transfer between it and its surroundings is:
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Correct answer: C — Zero.
In thermal equilibrium, there is no net flow of heat between the system and its surroundings; the rate of heat transfer is zero.
Q2. If two bodies, A and B, are in thermal contact and reach a final state of thermal equilibrium, which statement correctly describes their temperatures?
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Correct answer: A — The temperatures of both bodies are equal
Thermal equilibrium is achieved when the systems reach the same final temperature. Therefore, T_A = T_B.
Q3. If two bodies A and B are brought into contact and they reach thermal equilibrium, what must be true about their temperatures?
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Correct answer: A — T_A = T_B
The thermal equilibrium condition dictates that when systems reach equilibrium, they must share the same final temperature.
Q4. The Zeroth Law of Thermodynamics is fundamentally related to which concept?
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Correct answer: C — Thermal Equilibrium
The Zeroth Law establishes the concept of thermal equilibrium and defines the property of temperature. If two bodies are in thermal equilibrium with a third body, they are in thermal equilibrium with each other.
Q5. Two systems A and B are in thermal equilibrium. What is the temperature relationship between them?
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Correct answer: B — T_A = T_B
When two systems are in thermal equilibrium, they must have the same temperature. This is the fundamental property of thermal equilibrium.
Q6. If two objects are placed in thermal contact, thermal equilibrium is achieved when the net rate of heat transfer between them becomes:
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Correct answer: A — Zero
Thermal equilibrium is the state where there is no net flow of heat energy between the objects; hence, the net rate of heat transfer between them is zero.
Q7. Two bodies, A and B, are placed in thermal contact. If the system reaches thermal equilibrium, which of the following statements must be true?
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Correct answer: C — A and B are at the same temperature
Thermal equilibrium is achieved when there is no net heat transfer between the bodies. This condition is satisfied if and only if the two bodies are at the same final temperature.
Q8. Which physical quantity remains uniform throughout a system when it is in thermal equilibrium?
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Correct answer: D — Temperature
In thermal equilibrium, the temperature is uniform throughout the system, meaning it is the same at every point. Pressure and volume are not necessarily uniform unless the system is also defined as an ideal gas expansion, and internal energy is constant, but temperature is the defining uniform property at equilibrium.
Q9. When two bodies are placed in thermal contact, and one body is hotter than the other, heat flows from the hotter body to the cooler body until:
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Correct answer: A — Thermal equilibrium is established.
Heat spontaneously flows from a hotter object to a colder object, and this process continues until thermal equilibrium is reached, where the temperatures become equal.
Q10. The Zeroth Law of Thermodynamics is based on which concept?
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Correct answer: C — The concept of temperature.
The Zeroth Law establishes the concept of temperature as a measurable property that defines thermal equilibrium between systems.
Q11. If the internal energy of an isolated system remains constant while it is in thermal equilibrium, what does this imply?
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Correct answer: A — There is no net energy exchange with the surroundings.
Since the system is in equilibrium, it is in thermal contact with its surroundings, and the constant internal energy implies no net energy exchange (no heat flow) with the environment.
Q12. If two objects are not in thermal equilibrium, heat transfer will occur from the hotter object to the cooler object until equilibrium is reached. This process is governed by:
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Correct answer: A — The Second Law of Thermodynamics.
Heat flows spontaneously from a region of higher temperature to a region of lower temperature, which is a consequence of the Second Law of Thermodynamics.
Q13. If two bodies A and B are placed in thermal contact and reach equilibrium, which statement correctly describes their temperatures?
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Correct answer: D — T_A = T_B.
Thermal equilibrium dictates that the temperatures of all objects in thermal contact must become equal.
Q14. The state of thermal equilibrium implies that the net rate of heat transfer between the system and its surroundings is:
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Correct answer: C — Zero, indicating no net heat transfer.
Equilibrium means that the system has stopped exchanging energy with the surroundings, hence the net rate of heat transfer is zero.
Q15. What is the fundamental condition that must be satisfied for a system to be in thermal equilibrium with its surroundings?
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Correct answer: D — There is no net transfer of heat between the system and the surroundings.
Thermal equilibrium is reached when there is no net flow of thermal energy across the boundary of the system. This means the system and its surroundings are at the same temperature.
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