NEET Physics: the concept of temperature Practice Questions
15 free multiple-choice questions on the concept of temperature (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. When two objects are placed in thermal contact and allowed to reach equilibrium, what defines the temperature of both objects?
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Correct answer: B — The point where the net rate of heat transfer becomes zero.
Thermal equilibrium is reached when the objects have the same temperature, meaning the net rate of heat transfer between them is zero.
Q2. The relationship between the temperature scale Celsius (T_C) and the Kelvin scale (T_K) is given by:
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Correct answer: C — T_K = T_C + 273.15
The Kelvin scale is the absolute temperature scale. The conversion formula is T_K = T_C + 273.15.
Q3. Thermal expansion of solids and liquids is primarily a consequence of which effect related to temperature?
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Correct answer: D — Change in volume due to increased kinetic energy
As temperature increases, the average kinetic energy of the molecules increases, causing them to move faster and exert greater force, which results in the expansion of the substance (increase in volume).
Q4. Thermal equilibrium is the state where:
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Correct answer: B — There is no net flow of heat between two objects in contact.
Thermal equilibrium is the state where two or more systems in thermal contact cease to exchange net heat, meaning they have reached the same temperature.
Q5. Which of the following physical quantities is fundamentally used to measure the degree of hotness or coldness of a body?
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Correct answer: D — Temperature
Temperature is the macroscopic property that measures the degree of hotness or coldness of a system, directly related to the average kinetic energy of its constituent particles.
Q6. Which of the following statements best describes the difference between heat and temperature?
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Correct answer: C — Heat is the total energy transfer, temperature is the degree of hotness.
Heat is the total energy transferred due to a temperature difference, while temperature is the measure of the average kinetic energy of the particles, reflecting the degree of hotness or coldness.
Q7. In thermal equilibrium, what is the relationship between the temperatures of two systems in thermal contact?
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Correct answer: A — They are always equal
When two systems are in thermal equilibrium and in thermal contact, they must have the same temperature.
Q8. When two bodies are brought into thermal contact, the process eventually leads to a state where their temperatures are equal. This final state is known as:
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Correct answer: B — Thermal equilibrium
Thermal equilibrium is the state reached when two or more systems are in thermal contact and no further heat exchange occurs because they have the same temperature.
Q9. Which physical quantity is used to measure the degree of hotness or coldness of a body?
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Correct answer: C — Temperature
Temperature is the physical quantity used to measure the degree of hotness or coldness of a body, which is directly related to the average kinetic energy of its constituent particles.
Q10. Which scale is based on the triple point of water, historically and currently used in physics and chemistry?
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Correct answer: A — Kelvin
The Kelvin scale (K) is the absolute thermodynamic temperature scale, defined using the Boltzmann constant, making it the standard unit in scientific calculations.
Q11. If the kinetic energy of the constituent particles of a gas increases, what happens to the absolute temperature of the gas?
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Correct answer: C — It increases
Temperature is directly proportional to the average kinetic energy of the particles. An increase in kinetic energy directly implies an increase in temperature.
Q12. The property of thermal expansion states that most substances expand when heated. This expansion is primarily due to:
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Correct answer: B — Increase in the kinetic energy of the particles
When a substance is heated, the increased kinetic energy causes the molecules to move faster and occupy a larger volume, leading to expansion.
Q13. The concept of temperature is directly related to the average kinetic energy of the molecules within a substance. This relationship is established by which physical postulate?
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Correct answer: B — Zeroth Law of Thermodynamics
The Zeroth Law of Thermodynamics establishes the concept of temperature by stating that if two systems are in thermal equilibrium with a third system, they are in thermal equilibrium with each other, linking temperature to kinetic energy.
Q14. Which of the following physical properties is directly related to the direction of spontaneous heat flow between two objects?
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Correct answer: C — Temperature
Temperature is the property that determines the direction of spontaneous heat transfer. Heat always flows from a region of higher temperature to a region of lower temperature.
Q15. Which physical quantity fundamentally determines the average translational kinetic energy of the molecules in a substance?
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Correct answer: A — Temperature
Temperature is a measure of the average kinetic energy of the random motion of the molecules within a substance.
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