Behavior of Fluids Chapter 3 Section 2 ReminderFluids

Behavior of Fluids Chapter 3 Section 2

Reminder…Fluids • A substance that continually deforms (flows) under an applied stress • Includes liquids, gases, & plasmas

Reminder…Force A push or pull

Pressure • force exerted on a surface divided by the area where the force is exerted - the unit is Pa (Pascal) or N/m 2 • Formula: P=F÷A (P) pressure = (F) force ÷ (A) area

Pressure Example/Demo Stand Up!

Atmospheric Pressure • the force of air pushing down on Earth – we do not feel this pressure b/c the downward & upward forces are equal (Balanced Pressure) • Figure 18 Page 120 • How does the picture to the right demonstrate air pressure?

Variations in Atmospheric Pressure altitude → atmospheric pressure

Pascal’s Principle • Force is applied to a confined fluid, an increase in pressure is equally distributed to all parts of the fluid P=F÷A OR F=Px. A

Bernoulli’s Principle Speed → Pressure

Charles’ Law Temp → Pressure

Boyle’s Law Volume → Pressure

Pressure Summary PRESSURE force area temp. speed Volume studying

Buoyant Force • the upward force on an object in a liquid – due to greater pressure at deeper depths (like greater pressure at lower altitudes) • If buoyant force is > the weight of an object, it floats • If buoyant force is < the weight of an object, it sinks

Archimedes' Principle • The buoyant force on an object is equal to the weight of the fluid displaced by the object