In a hydraulic system, which statement correctly differentiates a hydraulic pump from a hydraulic motor?

• A. Motor converts hydraulic energy back to mechanical energy; pump converts mechanical energy to hydraulic energy.
• B. Pump converts mechanical energy to hydraulic pressure/flow; motor converts hydraulic energy back to mechanical energy.
• C. Pump converts hydraulic energy to mechanical energy; motor converts mechanical energy to hydraulic energy.
• D. Pump stores energy; motor dissipates energy.

Answer: (C)

In hydraulic systems, energy flow is defined by what each component does with energy: pumps take mechanical energy and turn it into hydraulic energy, while motors take hydraulic energy and turn it into mechanical energy. This means a pump uses power from a driver (like an engine or motor) to create pressurized fluid and flow that can do work elsewhere. A hydraulic motor, fed by that pressurized fluid, converts the fluid’s energy into rotational mechanical energy to drive a load.

So the correct distinction is that a pump converts mechanical energy to hydraulic energy, and a motor converts hydraulic energy to mechanical energy. This contrasts with statements that reverse the direction, or suggest energy storage or dissipation, which aren’t the primary roles of these components.