NEET Physics: convection Practice Questions
15 free multiple-choice questions on convection (Properties of Solids and Liquids) 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 rising column of heated air, what happens to the density of the air at the bottom compared to the top?
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Correct answer: B — Density decreases
When air is heated, it expands, causing the air molecules to move further apart, resulting in a decrease in density. This lower-density, cooler air rises.
Q2. In a liquid, when a region is heated, the resulting lower density fluid moves upwards. This movement is driven by:
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Correct answer: C — Increased kinetic energy
When a fluid is heated, its molecules gain kinetic energy, causing it to expand and become less dense, leading to upward movement (buoyancy).
Q3. Which property of fluids is directly responsible for the process of convection?
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Correct answer: D — Density
Convection is the transfer of heat through the movement of fluids (liquids or gases). This movement is driven by density differences, which are fundamentally related to temperature.
Q4. Which of the following scenarios primarily demonstrates natural convection?
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Correct answer: B — Formation of sea breezes
Natural convection occurs due to density variations caused by temperature differences within the fluid itself (e.g., cooling or heating of a fluid body).
Q5. Which mode of heat transfer primarily involves the movement of the fluid itself?
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Correct answer: C — Convection
Convection is the mode of heat transfer in which the heat is transferred by the movement of the heated particles of the fluid (liquid or gas).
Q6. If a fluid is forced to flow over a heated surface, the flow pattern is typically classified as:
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Correct answer: A — Forced convection
Forced convection occurs when an external force (like a pump or wind) causes the fluid to move, creating the flow pattern.
Q7. The process of heat transfer by convection is most effective in which type of medium?
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Correct answer: D — Liquids
Convection requires a fluid (liquid or gas) because heat transfer relies on the movement of that fluid particles. Solids generally rely on conduction.
Q8. Which medium is generally poorest at transferring heat via convection compared to solids?
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Correct answer: A — Solids
Solids are poor conductors of heat by convection because their particles are tightly packed and cannot move freely. Gases and liquids exhibit convection efficiently.
Q9. In a liquid undergoing convection, what happens to the fluid element when it is heated at the bottom?
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Correct answer: A — It becomes denser and sinks
When a fluid is heated, its temperature decreases, causing its density to increase. This denser fluid sinks, initiating the convective flow.
Q10. In a sealed container of liquid, if the bottom part is heated, what happens to the liquid due to convection?
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Correct answer: B — The heated liquid rises, and cooler liquid sinks.
The heated part of the liquid becomes less dense and rises, while the cooler, denser liquid sinks, creating a convection current.
Q11. In a confined liquid system, if the bottom surface is heated, the denser fluid near the bottom will move upwards. What is the primary driving force for this movement?
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Correct answer: D — Buoyancy generated by density differences.
When the bottom layer is heated, it becomes less dense and rises. This buoyant force causes the heated, less dense fluid to move upwards, establishing the convection current.
Q12. In a situation where a fluid is heated uniformly across its surface, what mechanism of heat transfer is most effective for heating the bulk interior?
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Correct answer: B — Convection
Convection is the dominant mechanism when the fluid is in motion or undergoing bulk movement to distribute the heat throughout the volume.
Q13. In the process of convection, which fluid component rises to the upper region?
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Correct answer: D — The hotter fluid
Hotter fluid is less dense than the surrounding fluid, causing it to rise, and cooler, denser fluid sinks, which drives the convection current.
Q14. Sea breeze phenomenon is an example of which type of heat transfer?
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Correct answer: C — Convection
The difference in air temperature between land and sea causes differential heating and cooling, leading to the movement of air masses, which is convection.
Q15. The primary mode of heat transfer in fluids is convection because:
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Correct answer: B — Fluids move and transfer thermal energy
Convection is the mechanism where energy is transported by the actual mass movement of the fluid particles, which is crucial for heat transfer in fluids.
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