When a liquid is flowing through a pipe, the velocity of the liquid is

Solution (By Examveda Team)

When a liquid flows through a pipe, the velocity distribution across the pipe's cross-section depends on the viscosity of the fluid and the nature of flow (whether laminar or turbulent). In laminar flow, which occurs at lower velocities and typically in small diameter pipes or at low Reynolds numbers, the velocity profile is parabolic.

Let's analyze each option:

Option A: "Maximum at the centre and minimum near the walls" - This is incorrect for laminar flow. In laminar flow, the velocity is highest at the centre of the pipe and decreases linearly to zero at the walls.

Option B: "Minimum at the centre and maximum near the walls" - This is incorrect. In laminar flow, the velocity is zero at the walls and increases parabolically to a maximum at the centre.

Option C: "Zero at the centre and maximum near the walls" - This is incorrect. In laminar flow, the velocity is maximum at the centre and decreases smoothly to zero at the walls.

Option D: "Maximum at the centre and zero near the walls" - This is correct for laminar flow. The velocity profile is parabolic, with the maximum velocity occurring at the centre of the pipe and decreasing to zero at the walls.

Therefore, the correct answer is Option D: Maximum at the centre and zero near the walls.