Which term uses liquid pressure?

• A. Hydraulics
• B. Pneumatics
• C. Lubrication
• D. Alignment

Answer: (A)

Using liquid pressure is hydraulics. Liquids transmit pressure when confined, and because you can change the piston sizes, a small force on a small area can become a much larger force on a bigger area. This is Pascal’s principle in action and is the reason hydraulics are used for heavy lifting, clamping, braking, and other tasks requiring large force with smooth, controllable motion. Pneumatics, by contrast, uses gas and is more compressible, so the force is less predictable and better suited to lighter operations. Lubrication reduces friction between moving parts, not pressure-driven actuation, and alignment is about positioning parts correctly rather than applying hydraulic pressure.