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When a fluid is at rest, the shear stress is-

When a fluid is at rest, the shear stress is- Correct Answer Zero

Concept:

  • A solid can resist shear stress by a static deformation; a fluid cannot
  • Any shear stress applied to a fluid, no matter how small, will result in motion of that fluid
  • The fluid moves and deforms continuously as long as the shear stress is applied
  • So, a fluid at rest must be in a state of zero shear stress

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