Booklet 3 Pressure :[ Flashcards
Pressure is defined as
The force per unit area (cm2 or m2)
How is pressure calculated
Pressure =force/area
Force is measured in
Newtons
Area is measured in
Meters squared (m2)
Pressure is measured in
(N/m2)
One pascal is measured in
1n/m2
To decrease pressure have
A larger surface area + reduce weight
To increase pressure you have to
Have a smaller surface area + increase weight
What is a fluid
A fluid is a substance that can easily flow. A fluid is able to change shape, therefore liquids and gases are both fluids.
In fluids molecules are constantly
Constantly moving in all directions and colliding with each other and any surface they meet. As each molecule Colin’s with a surface it exerts a force on the surface. All of the forces exerted by individual molecules in a fluid add together to make up the pressure entered by the fluid
Fluid pressure all around
Pressure but the air is called air pressure or atmospheric pressure. Air exerts pressure because it has mass.
Why doesn’t the air pressure crush you
Our body is mostly liquid and solid and has evolved to live with our atmospheric presssure our
Water pressure.. increases/decreases as
Water pressure increases as depth increases
Air pressure increases/decreases when
Air pressure decreases as elevation increases
Everything including liquids are made up of tiny particles. As the particles move around what happens
The particles move around and as they do this they collide with surfaces they come into contact with. The force of the particles hitting a surface causes pressure. Pressure comes from all directions.
