Explanation: The mechanical energy in a centrifugal pump that is driven by the impeller mounted on a shaft is measured by isentropic compression. Thus, the correct choice is isentropic compression.

Explanation: The centrifugal pump consists of two or more impellers. The impeller is mounted on one shaft or different shaft. A multistage centrifugal pump has more than two impellers. The multistage centrifugal is similar to the centrifugal pumps working.

Explanation: At each stage in the centrifugal pump, the fluid is directed to towards the centre. The energy usage in pumping installation is determined by Friction characteristics. Thus, it is the most suitable option.

Explanation: From the above, the factor that involves friction is determined by Darcy’s friction factor. The energy usage in pumping installation is determined by Friction characteristics. Thus, it is used in energy calculations in a pump.

Explanation: Darcy’s friction factor is dimensionless. It is one of the major applications in Fluid dynamics. The energy usage in pumping installation is determined by Friction characteristics. Thus, it is dimensionless.

Explanation: Formation of bubbles in an impeller is called as its as its cavities. These cavities develop intense shockwaves in the impeller.

Explanation: Centrifugal pump works by imparting kinetic energy to the liquid for rotating the impeller rotor.

Explanation: The full form of NPSH is Net positive suction head. The head added by the pump is a sum of static lift. Thus, corresponds to the efficient working of the pump. Higher the NPSH, more efficient the pump is.

Explanation: When the NPSH is low, it leads to cavitation. Cavitation is one of the major drawbacks that are seen in a centrifugal pump. There are various other problems as well. But, cavitation is due to low NPSH.

Explanation: Wear of impeller can be worsened by suspended solenoids. Wear and tear is one of the major drawbacks that are seen in a centrifugal pump. It affects the working of the impeller, thus resulting in an inefficient working.

Explanation: Reciprocating pump is the most efficient centrifugal pump because as the pressure increases, the flow rate remains constant.

Explanation: Corrosion in the pump is developed due to fluid properties. The flow of fluid plays a major role in determining the corrosion developed. Fluid flow can broadly be classified into laminar and turbulent depending on its Reynolds number.

Explanation: Over heating is a major problem faced in a pump. The temperature in a centrifugal pump is increases mainly due to the presence of low flow. Thus, by heating the fluid, the velocity of fluid flow increases.

Explanation: Cavitation in a boat propeller or a ship propeller leads to fast spinning due to the formation of bubbles.

Explanation: Yes, Lack of prime is a problem faced in centrifugal pump. It means that the centrifugal pump must be filled in order to operate in an effective way. The fluid must be filled in such a way so that it can pump.