Fluid Mechanics Glossary

Total pressure including atmospheric: P_absolute = P_gauge + P_atm. Always positive.

Buoyant force equals the weight of the displaced fluid: F_b = rho_fluid * V_displaced * g.

P + (1/2)*rho*v^2 + rho*g*h = constant along a streamline. Energy conservation for ideal fluid flow.

Net upward force on a submerged object due to fluid pressure differences. Equals weight of displaced fluid.

A1*v1 = A2*v2. Conservation of mass for incompressible fluid flow. Flow rate Q = Av is constant.

Volume of fluid passing a point per unit time: Q = A * v. SI unit: m^3/s.

Pressure relative to atmospheric: P_gauge = P_absolute - P_atm. Can be positive, negative, or zero.

Pressure at a depth depends only on depth, not on the shape or volume of the container.

Pressure applied to a confined, incompressible fluid is transmitted undiminished to every part of the fluid.

Force per unit area: P = F/A. In fluids, pressure acts equally in all directions at a given depth. SI unit: pascal (Pa).

A line tangent to the velocity of the fluid at every point. Bernoulli's equation applies along a streamline.

A fluid's internal resistance to flow. Causes energy dissipation. High viscosity: honey. Low viscosity: water.