Which component is essential in a centrifugal pump to impart energy to the fluid?

• A. Shaft
• B. Impeller
• C. Bearing
• D. Seal

Answer: (B)

In a centrifugal pump, the component that actually adds energy to the fluid is the impeller. Its rotating blades fling the fluid outward, which increases the fluid’s velocity and, through the pump’s geometry, raises its pressure as it moves into the volute or diffuser. The energy from the motor is thus converted into hydraulic energy by the impeller. The shaft simply transmits the rotational power to the impeller, while bearings support the shaft and seals prevent leakage. Without the impeller, the motor’s energy would not be transferred to the fluid to create flow and pressure.