Fluid Pressure fluid pressure is essential for us to do work –fluids always go from a point of high pressure to lower pressure –this movement of the fluid (a gas or liquid) can move objects along with it fluid pressure differences control weather air masses move from areas of high pressure to low pressure

Force is how hard you push… measured in Newtons (N) Area is how wide an area the force is spread over… usually measured in m 2 N/m 2 is called a pascal (Pa)

Compression Counts gases can exert a counterforce which absorbs force we can compress a gas, then release it to do work tires shock absorbers air mattress air bag nail gun air bag piston fire extinguisher air gun nail gun air bag piston fire extinguisher air gun

Compression of Liquids & Solids the particles of liquids and solids are closer together … so its harder to compress them liquids → power washer or even a nozzle on your garden hose solids → incompressible

Fluid Systems we use fluid under pressure to do work for us … how does that work?

Unbalanced Forces if the inside of a closed container is under pressure… the fluid will rapidly escape when the pressure is released! if the inside of a closed container experiences lower pressure the walls of the container will collapse

Atmospheric Pressure gravity keeps an envelope of air around the Earth but since air pressure outside your body is the same as inside… you don’t even it –unless you fly/climb high air pressure ↓ –or dive deep air pressure ↑ –we have a membrane in our ear to help us equalize when air pressure changes

Barometer used to measure air pressure as pressure increases the mercury is pushed higher as pressure decreases mercury falls lower

Fluid Systems

Hydraulics