Mr. Jackson Nov. 22, 2010

Pressure Fluids and Air have pressure The amount of force exerted over a given area is pressure Pressure is calculated as force/area The SI unit for pressure is the Pascal

Fluids exert pressure evenly in all directions In Cornell note system what is this phenomenon know as?

The gases are held in place by atmospheric pressure The higher you go the thinner the air becomes and therefore the harder it is to breathe.

Depth and Pressure As you go deeper into the ocean pressure becomes higher

Allowing us to Breathe The pressure differential between the outside air and in your lungs allows you to bring in air.

Tornados Tornados are very low pressure This causes objects to rush into the storm.

Buoyant Force The upward force that fluid exerts on all matter

What allows objects to Float If an objects density is less than that of the liquid it is in it will float If it is the same it will suspend If it is higher it will sink

Boats Boats have a really high density so they change their shape to allow more area of the boat to be in contact with the water This will allow the boat to float

Submarines Submarines add water to ballast tanks to change its mass and to sink lower into the water. Fish use a similar method but they fill a swim bladder with air to rise in the water

Bernoulli’s Principle As the speed of a moving fluid increases the fluids pressure decreases. This allows the wings of an airplane to create Lift.

Factors that Affect Flight Lift Thrust- the forward motion created by engines Wing Size Drag- the force opposing motion Irregular Drag is know as turbulence

Pascal’s Principle Hydraulic devices use this principle When the pressure of the fluid changes it expands equally in all directions Hydraulic devices multiply force many times. Brakes are the biggest example of hydraulics.