Physics and Math Ch4 Flashcards
Fluids
Substances that have the ability to flow and conform to the shape of their containers
- can exert perpendicular forces, but not shear forces
Solids
Do not flow and they retain their shape regardless of their containers
Density
The mans per unit volume of a substance
Pressure
A measure of force per unit area
- scalar
- the pressure exerted by a gas against the walls of its container will always be perpendicular to the container walls
Absolute pressure
the sum of all pressures at a certain point within a fluid; it is equal to the pressure at the surface of the fluid + the pressure due to the fluid itself
Gauge Pressure
The name for the difference between absolute pressure and atmospheric pressure
- In liquids, gauge pressure is caused by the weight of the liquid above the point of measurement
Pascal’s Principle
A reassure applied to an incompressible fluid will be distributed undiminished throughout the entire volume of the fluid
Hydraulic Machines
Operate based on the application of pascal’s principle to generate a mechanical advantageA
Archimedes’ principle
When an object is placed in a fluid, the fluid generates a buoyant force against the object that is equal to the weight of the fluid displaced by the object
- Direction always opposite to gravity
Cohesive forces
- Attractive force experienced between other molecules of the same fluid
- Cause surface tension
Adhesive forces
Attractive force that occurc between molecules of different materials
Surface tension
Causes the liquid to form a thin but strong layer at the liquids surface
Viscosity
A measurement of a fluids internal friction
Viscous drag
a nonconservative force generated by viscosity
Continuity Equation
A statement of the conservation of mass as applied to fluid dynamics
