Which one of the following statements is correct? When a fluid passes through the narrow part of nonuniform pipe,
its velocity and pressure both increase
its velocity and pressure both decrease
its velocity decreases but its pressure increases
its velocity increases but its pressure decreases
Consider two points A and B in the pipe at the same horizontal level. At point A, let be the area of cross-section of the pipe, the velocity of fluid flow and the fluid pressure. Let and be the corresponding quantities at point B. Then from Bernoulli's theorem, we have
If , it follows from continuity equation , that . From Eq. (i), it follows that . Hence, at the narrow part of the pipe, the fluid velocity increases but its pressure decreases,