Chapter 5: Fluid Mechanics

Density

The amount of matter per unit volume; it measures the compactness of how much mass an object occupies.

Formula for Density

Density = mass/volume

Pressure

The ratio of force to the area over which the force is distributed; can be calculated using the formula pressure = force/area.

Formula for pressure

Pressure = force/area

Buoyant Force

The net upward force that fluid exerts on an immersed object.

Archimedes’ Principle

An immersed body is buoyed up by a force equal to the weight of the fluid it displaces. This applies to liquids and gasses

Principle of Floatation

A floating object displaces a weight of fluid equal to its own weight.

Boyle’s Law

The product of pressure and volume is constant for a given mass of confined gas at the same temperature; expressed as P1V1 = P2V2.

Atmospheric Pressure

The pressure exerted against bodies in the atmosphere, resulting from the weight of air pressing down from above.

Barometer

Any device that measures atmospheric pressure. Thermometer,

Fluid Mechanics

The study of fluids (liquids and gases) and the forces that act on them.

Weight Density

The weight of a substance per unit volume, often expressed in pounds per cubic foot.

Pascal’s Principle

A change in pressure at any point in an enclosed fluid at rest is transmitted undiminished to all points in the fluid.

Bernoulli’s Principle

States that where the speed of a fluid increases, the internal pressure in the fluid decreases.

Liquid Pressure

Liquid pressure = weight x depth