Fluids

16A Properties of Fluids

• Fluids and Pressure

  • Fluid: any substance that can flow

  • Pressure: a measurement of the amount of force acting upon a unit area

  • Pascal: the derived SI unit of pressure

  • Pascal’s Principle: the principle that states that pressure applied to a fluid is transmitted throughout the fluid

• Buoyancy: the tendency of an object to float when immersed in a fluid

• Buoyant Force

  • Buoyant Force: the upward force caused by the displacement of a fluid

  • Archimedes’s Principle: the principle that states that an immersed object displaces an amount of fluid equal to its volume and that the weight of the displaced fluid is equal to the buoyant force acting on the object

  • Neutral Buoyancy: the condition when an object submerged in a fluid neither ascends nor descends because its density is equal to that of the fluid

• Viscosity: a measure of a fluid’s resistance to flowing

16B Gas Laws

• Boyle’s Law: a gas law that the pressure and volume of a sample of gas at a constant temperature are inversely proportional

• Pressure and Volume

1. Collisions

2. Gas Pressure

3. Volume Goes Down, Pressure Goes

4. Volume Goes Up, Pressure Goes Down

• Charles’s Law: a gas law stating that the volume and absolute (Kelvin) temperature of a sample of gas at constant pressure are directly proportional

• Gay-Lussac’s Law: a gas law stating that the pressure and absolute (Kelvin) temperature of a sample of gas at a constant volume are directly proportional

• Combined Gas Law: a gas law that states that the ratio of the product of a gas sample’s pressure and volume to its absolute (Kelvin) temperature is constant

16C Fluid Mechanics

• Hydraulics: the branch of physics concerned with the forces within and work done by liquids

• Bernoulli’s Principle: the principle that states that the fluid pressure of a flowing fluid decreases as its speed increases