Fluid property – resistance to relative layer motion The property of a liquid that offers resistance to the movement of one layer over another adjacent layer is called:
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Asurface tension
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Bcompressibility
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Ccapillarity
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Dviscosity
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Eelasticity
Answer
Correct Answer: viscosity
Explanation
Introduction:Several fluid properties influence different phenomena. This question seeks the term for internal friction that resists sliding motion between neighbouring fluid layers.
Given Data / Assumptions:
- Layers experience relative motion under shear.
- Liquid is Newtonian for simplicity.
- External factors like temperature may affect property magnitude but not the definition.
Concept / Approach:Viscosity quantifies resistance to deformation in shear. The higher the viscosity, the larger the shear stress required to maintain a given velocity gradient across layers.
Step-by-Step Solution:1) Identify the phenomenon: resistance to sliding between layers.2) Recall the constitutive law τ = μ * (du/dy).3) The property μ (dynamic viscosity) is therefore the correct descriptor.
Verification / Alternative check:Everyday comparison—water vs. honey—illustrates that higher μ liquids flow more slowly for the same driving head.
Why Other Options Are Wrong:
- Surface tension governs interfaces, not bulk shear.
- Compressibility relates to volume change with pressure.
- Capillarity concerns surface tension/meniscus effects in small tubes.
- Elasticity describes solids or transient liquid compressibility, not steady shear resistance.
Common Pitfalls:Mixing up ν (m^2/s) with μ (Pa·s); both increase resistance, but units and meaning differ.
Final Answer:viscosity