Exam Question

### (a) Centrifugal Pumps vs. Turbo-Blowers: Handling Air
The fundamental reason centrifugal pumps cannot handle air for priming while turbo-blowers can, despite operating on the same centrifugal principle, lies in the vast difference in the density of the fluids they are designed to move (liquid vs. gas) and the resulting magnitude of the centrifugal force generated.
1. **Principle of Operation**: Both machines use a rotating impeller to impart kinetic energy to a fluid. This energy is converted into pressure potential as the fluid is thrown outwards by centrifugal force. The pressure at the impeller eye is reduced, creating suction.
2. **Effect of Fluid Density**: The centrifugal force ($$F_c$$) generated is directly proportional to the mass ($$m$$) of the fluid within the impeller vanes at any given time ($$F_c = m \omega^2 r$$).