[amp_mcq option1=”frictional force” option2=”viscosity” option3=”surface friction” option4=”all of the above” correct=”option4″]
The correct answer is D. all of the above.
In order for flow to take place between two points in a pipeline, the differential pressure between these points must be more than the frictional force, viscosity, and surface friction.
Frictional force is the force that opposes the relative motion of two surfaces in contact. It is caused by the roughness of the surfaces and the adhesion between them. Viscosity is the resistance of a fluid to flow. It is caused by the internal friction of the molecules in the fluid. Surface friction is the friction between a fluid and a solid surface. It is caused by the adhesion between the fluid and the solid surface.
The differential pressure is the difference in pressure between two points in a fluid. It is the driving force for fluid flow. The greater the differential pressure, the greater the flow rate.
If the differential pressure is not greater than the frictional force, viscosity, and surface friction, then the fluid will not flow.