A fluid is defined as one which:a)is solid-like when there is no moti...
The distinction between a solid and a fluid is made based on a substance’s ability to resist an applied shear (tangential) stress that tends to change its shape.
A solid can resist an applied shear by deforming its shape, whereas a fluid deforms continuously under the influence of shear stress, no matter how small its shape is.
A fluid can be defined as a substance that is capable of flowing and changing its shape according to the surrounding without offering internal resistance. Liquid offers no resistance to change of shape, and it conforms to the shape of its surrounding.
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A fluid is defined as one which:a)is solid-like when there is no moti...
Definition of a Fluid:
A fluid is a substance that can flow and conform to the shape of its container. It can be either a liquid or a gas. Unlike solids, fluids do not have a fixed shape and can easily deform under the influence of external forces.
Explanation of the Correct Answer (Option B):
Option B states that a fluid deforms continuously when subjected to shear stress. Let's break down this answer further to understand why it is the correct choice.
Shear Stress:
Shear stress is the force per unit area that acts parallel to the surface of an object. When a fluid is subjected to shear stress, it experiences a continuous deformation.
Continuous Deformation:
Unlike solids, which resist deformation and maintain their shape, fluids can easily deform when subjected to external forces. When a fluid is subjected to shear stress, its layers or particles slip and slide past each other, resulting in a continuous deformation.
Shear Force and Viscosity:
The ability of a fluid to deform under shear stress is related to its viscosity. Viscosity is a measure of a fluid's resistance to flow. Fluids with high viscosity, such as honey or molasses, offer more resistance to shear stress and deform less easily. On the other hand, fluids with low viscosity, such as water or air, flow more easily and deform readily under shear stress.
Conclusion:
In summary, a fluid is defined as a substance that can flow and conform to the shape of its container. Unlike solids, fluids deform continuously when subjected to shear stress. This ability to deform under shear stress is what distinguishes fluids from solids. Therefore, option B - "deforms continuously when subjected to shear stress" - is the correct answer.