What aspect does a pump curve specifically display?

A pump curve is a graphical representation that illustrates the relationship between flow rates and pump efficiency. It provides critical information about how a pump performs across different flow conditions. The curve typically shows various operating points at which the pump can deliver a certain flow rate while maintaining optimal efficiency.

The primary purpose of the pump curve is to assist operators in selecting the appropriate pump for specific applications by showing how much flow can be delivered at different system pressures. Additionally, the efficiency of the pump—how effectively it converts input power into fluid energy—is explicitly displayed on the curve. Understanding these aspects is essential for ensuring that the pump operates within its best range for maximum energy savings and longevity.

While other options touch on important aspects related to pumps, they do not specifically pertain to the key elements of a pump curve. Efficiency is indeed part of the data presented, but the most critical feature is the understanding of flow rates in relation to that efficiency, making flow rates and pump efficiency the correct focus of a pump curve.