Hydraulics And Fluid Mechanics - Study Mode

Explanation

Solution: Viscosity is a measure of a fluid's resistance to flow. It is affected by temperature differently for liquids and gases. Effect of Temperature on Liquids: - As temperature increases, the kinetic energy of liquid molecules increases. This weakens intermolecular forces, making it easier for the liquid to flow. As a result, the viscosity of a liquid decreases with an increase in temperature. Effect of Temperature on Gases: - In gases, viscosity is primarily due to the momentum transfer between molecules. As temperature increases, the molecular collisions increase, leading to higher viscosity. Analysis of Options: - Option A: Increase in viscosity of gas → Correct for gases, but the question focuses on general fluid behavior. Option B: Increase in viscosity of liquid → Incorrect, as liquid viscosity decreases with temperature. Option C: Decrease in viscosity of gas → Incorrect, as gas viscosity increases with temperature. Option D: Decrease in viscosity of liquid → Correct, as liquid viscosity reduces when temperature rises. Conclusion : The correct answer is Option D: decrease in viscosity of liquid because higher temperatures reduce intermolecular forces in liquids, allowing them to flow more easily.