2) The flow through a cylindrical pipe with a circular cross-section must always be a uniform flow. 3) The main difference between rigid body mechanics and fluid mechanics is that the term of...

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Extracted text: 2) The flow through a cylindrical pipe with a circular cross-section must always be a uniform flow. 3) The main difference between rigid body mechanics and fluid mechanics is that the term of convective acceleration does not exist in rigid body mechanics. 4) The temporal average of the velocity components perpendicular to the pipe wall in turbulent flow in a circular pipe is zero.