What is one way to calculate the efficiency of a pump?

Calculating the efficiency of a pump is an important aspect of evaluating its performance. The efficiency of a pump is determined by the ratio of the useful work output (or hydraulic power) it performs to the energy input it requires to operate.

In this context, output power divided by input power provides a clear way to quantify how effectively the pump converts the input energy into useful work. The output power is usually represented by the hydraulic power, which reflects the energy used for moving the fluid, while the input power refers to the energy supplied to the pump, typically from an electric motor or other prime mover.

Using this ratio allows for easy comparison of different pumps, and understanding how much of the input energy is successfully converted into mechanical work can provide insights into operational efficiency. An efficient pump will have a ratio closer to 1 (or 100% when expressed as a percentage), indicating that most of the energy supplied is being effectively utilized rather than lost to factors such as friction or turbulence.

The other options do not accurately reflect the definition of pump efficiency, as they either mix different concepts or provide irrelevant calculations. By focusing on the output power relative to the input power, you capture the essence of pump efficiency directly and effectively.