Q93
General SciencePhysics
Hydraulic press is based on
- a.Archimedes law
- b.Pascal's law
- c.Reynold's law
- d.Bernouli's law
Answer: (B) Pascal's law
Pascal's law states that pressure applied to an enclosed incompressible fluid is transmitted undiminished in all directions; a small force on a small piston therefore produces a large force on a big piston ($F_2=F_1\frac{A_2}{A_1}$). Hydraulic presses, lifts, jacks and brakes all use it. Archimedes' principle deals with buoyancy (ships, hydrometer), Bernoulli's principle relates pressure and speed in a flowing fluid (aeroplane lift, atomiser, venturimeter), and the Reynolds number tells whether a flow is streamline or turbulent.