Copy the black, just read the red.

fluid = a substance that can flow and take shape of its container

All liquids and gases = fluids

Compressible Fluid = volume can change Gas= compressible fluid because its particles

are far apart

Incompressible fluid- volume cannot be varied

Liquids = incompressible fluid because its particles are close together

Gives a transmission of force from one particle to another inside the substance (like dominos)

syringes

S- space A- attraction M- movement E- energy

gas S- lots

A- no bonds

M- zip quickly

E - high

liquid S- close

A- weak bonds

M- slide past

E - medium

Gels & pastes = fluids only if they flow and take on the shape of their containers

Powders –sugar, sand = not fluids even though they have no form and flow

They do not naturally assume the shape of the container *

Rinse out a 2 L pop bottle and then fill it to the top.

Place an eye dropper into the water and fill ¼ full with water (just to let it sit at the surface of the water in the bottle.)

Cap the bottle tightly. Compress the bottle and see what happens to

the eye dropper.

Why does the Bottle Diver dive? Can you make the diver stay in one place in

the bottle? What is happening at this point?

If you pour out half of the water in the bottle, it becomes much harder to sink the diver.  Why?

Pressure =result of force applied perpendicularly to a surface

unit of measure = pascals (Pa)

-an action that changes the movement of an object e.g. Stop, move, slow

When apply force on a fluid = fluid exerts a force on whatever contains it (bottle divers)

balloons

Variation in force Result

Force incr. P incr.

Force Decr. P decr.

Variation in S.A Result

S.A. P

S.A. P

F

P A

P= pressure in pascals- Pa F= force in neutons - N A= surface area in square metres –m2

Just be able to explain it

If a person stands on a nail, the foot will be punctured

However, if the person lays down on a bed of nails the skin would not be broken.

Why?

There is more pressure per square centimetre exerted under the heel of a stiletto shoe than under the Empire State Building?

Bill Nye Fluids

1. mass of fluid above the object. More fluid above = greater force = greater

pressure Using Particle

Theory, WHY?

Water towers are raised to use gravity and the mass of the water to increase the pressure of the water leaving the tower.

2. density of liquid Higher density = greater force = greater

pressure Using Particle Theory, WHY?

Optic nerve damage in the eye caused by increased pressure inside the eye

When particles of compressible fluids collide = exert a force on the obstacle.

collisions = P

as pressure increases Volume decreases

As pressure decreases volume increases

as volume increases Pressure decreases

As volume decreases Pressure increases

1. particles = more collide = P

2. temperature = E to particles = move more and collide more = P

3. volume = same number of particles in less space = collide more = P

As ascend a mountain = external pressure decreases & eardrum swells

can affect hearing, and can hurt air enters the Eustachian tubes (between ears

and throat), the pressure is equalized may notice a POP as this happens and the

discomfort will stop.

1. Fluid ALWAYS moves from high pressure to low pressure

2. Pressure applied to the surface of a fluid inside a closed container = uniformly distributed to every part of the fluid

3. A transfer of pressure in a fluid can increase the force involved.

Your heart is a pump that regulates the pressures of the blood in the body

Blood pressure in arteries ranges from 120 mm Hg when the heart contracts and pushes the blood out to 75 mm Hg when the heart is at rest

When you breathe your diaphragm contracts and lowers into your abdomen. This creates a larger volume inside the chest and a lower pressure in your lungs than outside. As air flows from high P to low P, air rushes in.

The reverse happens when you exhale.

Read page 112 in your Toolbox on how to create a Concept Map

Using the ALL the words on page 87 to create a concept map for Chapter 3 of your textbook.

You can use your notes too.

Read the article on page 88 and answer the questions at the bottom.

Remember this article when we discuss Respiration later.

Bill Nye- Pressure