Which of the following statements is TRUE about centrifugal pumps?

Centrifugal pumps are designed to move fluids by converting rotational kinetic energy into hydrodynamic energy. One important characteristic of these pumps is that they exhibit varying efficiency levels depending on the head they are operating under. As the head increases, the friction losses within the pump and the fluid itself can lead to a decrease in overall efficiency. This is often due to factors such as increased viscosity and turbulence, which consume more energy and reduce the pump's ability to effectively move fluid. Therefore, it's true that centrifugal pumps generally become less efficient at high heads, making this statement accurate within the context of their operational characteristics.

While some centrifugal pumps can handle low heads fairly well, their performance may not be optimal in those conditions, especially if operating far from their best efficiency point. Similarly, they do not work equally well at all heads, as each pump has a specific curve that defines its performance across different operating conditions. Lastly, the notion of requiring less energy at high heads typically doesn't apply; instead, they tend to require more energy due to the increased demands on performance at higher operational points.