P6

• fluids are substances that continually and smoothly deforms when shear stress is applied to it
• fluid flows when acted upon by a force
• density is also known as mass density or specific mass, and is the ratio of the mass of an object to its volume.
• when density is greater than 1, it will sink
• when density is less than 1, it will float
• specific weight is also known as weight density. It is a measure of weight of a fluid occupying one cubic meter of space
• specific gravity is also called relative density, it is the ratio of the density of a substance to the density of water.
• pressure does not depend on the shape and size of the container
• Weight density is used more in liquid pressure, while mass is used in solids
• gauge pressure is defined as the pressure above or below the atmospheric pressure
• absolute pressure is the total pressure or true pressure
• Pascal's principle states that pressure applied to an enclosed fluid is transmitted equally and undiminished to every portion of the fluid and the walls of the containing vessel
• archimedes' principle states that a body wholly or partially submerged into a fluid is buoyed up by a force which is equal to the weight of the displaced fluid
• when buoyant force is greater than the weight of object, it will float
• when buoyant force is less than the weight of an object, it will sink
• Force exerted by fluid pressure

  Acts perpendicular to the walls of its container and those the walls exert on the fluid
• Force exerted by fluid pressure at a given depth

  The same in all directions
• Pressure in a liquid

  Acts in all directions at a point in the liquid