Bell Ringer 2-19-10 What is the formula for pressure? What place on earth is there the greatest pressure? The least pressure? What is the SI Unit for density? What causes your ears to pop when going up in a airplane or swimming towards the bottom of a swimming pool? If an object floats, it is (less, more) dense than the fluid it’s in.

Videos Titanic

Chapter 11 Sections 3 and 4

Pascal’s Principle

Pascal’s Principle Pascal’s Principle states when force is applied to a confined fluid, the change in pressure is transmitted equally to all parts of the fluid. P. 389

Using Pascal’s Principle: Figure 15

Hydraulic System Hydraulic system is a system that multiplies force by applying the force to a small area. The increase in pressure is then transmitted to another part of the confined fluid, which pushes on a larger surface area. Pressure = F Larger force a larger area

Bernoulli’s Principle Bernoulli’s Principle is the rule that a stream of fast-moving fluid exerts less pressure than the surrounding fluid.

Examples Airplane flying Chimney Frisbee flying through the air

Fluids move from areas of higher pressure to areas of lower pressure. Higher  Lower Pressure Pressure

Lift is an upward force.