Question

Given below are two statements
Statement I: Pump coverts mechanical power to fluid power and actuator converts hydraulic power to mechanical power
Statement II: Hydraulic cylinder provides rotary mechanical power and hydraulic motor provides linear mechanical power
In light of the above statements, choose the most appropriate answer from the options given below

• A. Both Statement I and Statement II are correct
• B. Both Statement I and Statement II are incorrect
• C. Statement I is correct but Statement II is incorrect
• D. Statement I is incorrect but Statement II is correct

Hint:

Associate the component name with its motion:
• Cylinder \(\rightarrow\) Piston moving in a straight line \(\rightarrow\) Linear motion.
• Motor \(\rightarrow\) Shaft spinning \(\rightarrow\) Rotary motion. This simple association helps avoid confusion between the two main types of hydraulic actuators.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
This question tests the fundamental knowledge of components in a hydraulic system, specifically the function of pumps and actuators (cylinders and motors) and the type of motion they produce.

Step 2: Detailed Explanation:
Analyze Statement I: "Pump coverts mechanical power to fluid power and actuator converts hydraulic power to mechanical power".
This statement is correct.

• A pump is the heart of a hydraulic system. It takes mechanical energy (e.g., from a rotating shaft of an engine or electric motor) and converts it into hydraulic energy in the form of fluid flow and pressure.

• An actuator is the component that does the work. It takes the fluid power (flow and pressure) from the pump and converts it back into mechanical energy (force and motion). Both hydraulic cylinders and motors are types of actuators.
Analyze Statement II: "Hydraulic cylinder provides rotary mechanical power and hydraulic motor provides linear mechanical power".
This statement is incorrect. The roles are reversed.

• A hydraulic cylinder (or ram) is a linear actuator. It produces a force in a straight line (push or pull), resulting in linear mechanical power. Think of the arm of an excavator.

• A hydraulic motor is a rotary actuator. It produces torque and continuous rotation, resulting in rotary mechanical power. Think of the drive wheels on some construction equipment or the spinning auger on a machine.
The statement incorrectly swaps the types of motion produced by cylinders and motors.
Conclusion:
Statement I is a correct description of the energy conversions in a hydraulic system. Statement II incorrectly describes the output of hydraulic cylinders and motors. Therefore, Statement I is correct and Statement II is incorrect.

Step 3: Final Answer:
Statement I is correct but Statement II is incorrect.