Question

The type of centrifugal pump preferred for a specific speed of $20\ r.p.m.\ $ is
(A) Slow speed pump with radial flow at outlet
(B) Medium speed pump with radial flow at outlet
(C) High speed pump with radial flow at outlet
(D) High speed pump with axial flow at outlet

Answer 1

Hint: Centrifugal force is a force that arises from the body's inertia and appears to act on a body that is moving in a circular path which is directed away from the centre around which the body is moving. Centrifugal force unit is Newton. The centrifugal force drives the object away from the centre. It is a fictitious force, peculiar to a particle moving on a circular path, that has the same magnitude and dimensions as the force that keeps the particle on its circular path (the centripetal force) but points in the opposite direction. Based on this concept we have to solve this question.

Complete step-by-step answer:
The centrifugal force is very real if you are in a rotating reference frame. However, the centrifugal force is an inertial force, meaning that it is caused by the motion of the frame of reference itself and not by any external force.
The concept of centrifugal force can be applied in rotating devices, such as centrifuges, centrifugal pumps, centrifugal governors, and centrifugal clutches, and in centrifugal railways, planetary orbits and banked curves, when they are analysed in a rotating coordinate system.
The type of centrifugal pump preferred for a specific speed of $20\ r.p.m.\ $ is slow pump with radial flow at outlet. Low-specific speed radial flow impellers hydraulic head principally through centrifugal force.

Hence, the correct answer is Option A.

Note: We know that the basic principle behind any hydraulic system is very simple - pressure applied anywhere to a body of fluid causes a force to be transmitted equally in all directions, with the force acting at right angles to any surface in contact with the fluid. A hydraulic press works on the principle of Pascal's law, which states that when pressure is applied to a confined fluid, the pressure change occurs throughout the entire fluid. Within the hydraulic press, there is a piston that works as a pump, that provides a modest mechanical force to a small area of the sample.
We know that a hydraulic press is used for almost all industrial purposes. But basically, it is used for transforming metallic objects into sheets of metal. In other industries, it is used for the thinning of glass, making powders in case of the cosmetic industry and for forming the tablets for medical use.