Characteristics of Fluids Archimedes’ Principle Pascal’s Principle Bernoulli’s Principle
How do fluids respond to weight and/or pressure? Essential Question How do fluids respond to weight and/or pressure?
Buoyant Force Buoyant Force: The upward force or push a fluid exerts on an object in that fluid. Caused by a difference in pressure. The deeper you go in a fluid the higher the pressure. (remember the tennis ball container) If the buoyant force ↑ is less than the objects weight ↓ it will sink. If the buoyant force ↑ is equal to the objects weight ↓ it will float. If the buoyant force ↑ is greater than the objects weight ↓ it will rise up. show pHet Sim: Ballons and Buoyancy
Archimedes' Principle Archimedes Principle: The buoyant force on an object is equal to the weight of the fluid displaced by the object. Weight of object = Weight of fluid displaced Object floats Weight of object > Weight of fluid displaced Object sinks Weight of object ‹ Weight of fluid displaced Object rises up What is the fluid being displaced in this picture? What is the weight of this fluid?
Archimedes Principle
Demo of Arch. Principle Object Mass Weight of Object (m x .00982) Weight of object = Weight of fluid displaced Object floats Weight of object > Weight of fluid displaced Object sinks Weight of object ‹ Weight of fluid displaced Object rises up Demo of Arch. Principle Object Mass Weight of Object (m x .00982) Mass of Displaced Water Weight of Water Candle Plastic Cube Metal Cylinder Gas Spigot
Pascal’s Principle Pascal’s Principle: Pressure applied to a fluid is spread evenly and unchanged throughout the fluid. Example: When you squeeze one end of a balloon the other end pops out. Wherever you squeeze a tube of toothpaste the paste comes out.
Hydraulic Lift
Hydraulic Lift Drawing
Bernoulli’s Principle Bernoulli’s Principle: As the speed of a fluid increases the pressure exerted by the fluid sideways decreases. Example: blow over the top of a piece of paper Airplane Wing Blowing Between 2 pop cans
Airplane Wing
Airplane Wing
Pop Can Drawing