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Density= density is how dense a fluid is

Density can be measured through mass divided by volumeYou can tell many things about a fluid depending on how dense it is

For example if you know the density you can easily see which fluids can

float atop one another a good example of this is our density towersThe more dense a fluid is the more packed together the particles are and

the less dense the less particles are packed into one spaceNote that particles can also be different sizesPressure=pressure is a measure of force acting perpendicular to a unit

area.

If the force is increased the pressure is increased as wellFor pressure the force is measured in newtons 1 newton is 100 grams and

the area is often measured in square meters=n/m2 or also known as a

pascal or a kilo pascal 1 kilo pascal is im not too sure:pPressure and particle theory=the particle theory states that particles are

constantly moving and move very fast with a great deal of energy and

move slower if they have less energy. When particles move there is always

a chance that they will bump into eachother like bumper cars. When the

collision occurs the particles move apart and there is only an empty space

left inbetween them.Why do fluids such as juice in a cup or air in a tire seem to be still when all

the particles are moving? Moving particles exert a force in the direction of

their motion. Fluid particles are moving in all directions at all times, thus

most of the forces cancel each other out, but some are not cancelled.

These forces are exerted onto the walls of the container therefore causing

pressure. But what happens if there is a hole in the cup or container? In

which direction does the fluid flow? Regardless of where the crack or hole

is the result is always the same, it flows out. This indicates that the

pressure of a fluid is exerted equally in all directions.The particles in the inner wall of the container apply pressure on the fluid

to stay inside the container, the particles of the fluid press against the

container with an equal force.

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Compressibility=the particles in a fluid push against each other until

something more ridgid such as the walls of their container exertes a force

in the opposite direction. But what happens when pressure is placed on a

liquid in an enclosed area? For example a water bottle filled with water,can the particles move closer together?According to particle theory, the amount of empty space in between

particles depend on 2 factors.1=the physical state of the substance whether the substance is a solid

liquid or gas2=the amount of energy the particles have.In general the amount of space in between liquid particles is very small

while those of gases are much larger. Therefore this gives gases the

unique ability to be compressed in to a smaller area for the particles have

more space in between them to be compressed.Solids and liquids on the other hand are almost known as incompressible

and so when force is applied on the solids and liquids the applied force is

transmitted from one particle to the next kind of like dominos.Archidemes principal= the buoyant force acting on an object equals the

weight (force of gravity) of the fluid displaced by the object. An example ofthis is if you displace 1l of fluid from a container the object that displaced

the fluid will have the same volume as water but will not have the same

mass, so if the object is heavier than the water that is displaced the object

will sink and if it is lighter it will float, if its the same this is know as neutral

buoyancy where the object does not float nor sink. An example of neutral

buoyancy is submarines and how the want to stay the same level in the

water at all times not sinking nor floating to the surface.Every time you placer an object in a fluid the fluid will be displaced

depending on the overall volume of the object you have placed in the fluid

and the mass of the substance displaced and the object that has displaced

the fluid.

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Also if you look at the measuring buoyancy activity in the booklet before

you can also see in the images that in this case the more dense an object

is the more buoyant force it has. Buoyant force for liquids can be measured

by the weight of the object out of the fluid subtracted by the weight of the

object in the fluid and with that you get the buoyant force of the liquid.Gases have the ability to be compressed to almost 1/10th of their of their

original volume.Hydraulics and pneumatics= hydraulics work on liquids usually water while

pneumatics mainly work on gases. Hydraulics work when two or more

pistons are attached and filled with either a liquid or a gas so that when

you push the master piston containing the liquid all of the force would be

sent to the second piston therefore exerting the force onto the second

piston allowing it to push, pull, drag etc, hydraulics are more powerful than

pneumatics because when we talked about gases earlier we know that

gases have the ability to be compressed so when we push the master

piston of a pneumatics machine not all of the force is transferred to the

second piston because the gases for the second piston are compressed

therefore the energy going to the secong piston is reduced. Hydraulics on

the other hand run on liquids and liquids are almost incompressible so all

of the force is transferred to the second piston right away and none of the

energy being transferred is wasted.

For these systems the pipe in which the liquid is transferred can also fork

into different and numerous paths therefore the master piston can control

more than one slave piston but for each of the slave pistons the force that

they exert will be reduced because it would be shared with another slave

piston.One key way to increase the force exerted from the second piston is to

increase the surface area( I think) of the slave piston therefore if the

master piston has a height of 9 inches and the slave piston has a height of

3 inches and the master has a base surface area or 3cm2 and the slave

has a base of 9cm2 the slave has a base which is 3 times bigger than that

of the slave therefore the force which is applided to the master will be

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amplified by 3 times when coming out of the slave piston. Also since the

base is 3 times larger you woul have to push the master piston 3 inches

with 100 pounds of force to get the slave piston with a wider base surface

area 1 inch high with 100x3=300 pounds of force.Another way to make it stronger is to drain a hydraulics system of all air

bubbles so no force is lost with compressed gases.