Pressure Flashcards
how to calculate the pressure at the surface of a fluid?
pressure = force/area
how to work out pressure due to a column of liquid?
pressure = height x density x gravitational field strength
how does pressure cause upthrust?
An object that is partly, or completely, submerged experiences a greater pressure on its bottom surface than on its top surface. This causes a resultant force upwards
what is the cause of atmospheric pressure and how does it change with height?
Air pressure is caused by the weight of the air molecules above
As elevation increases, there is less overlying atmospheric mass, so atmospheric pressure decreases with increasing elevation
define a fluid
any liquid or gas
how is pressure caused in a fluid?
pressure in a liquid is due to the weight of the column of water above. Since the particles in a liquid are tightly packed, this pressure acts in all directions
pressure equation
force normal to a surface/area of surface
pressure equation 2
pressure = height of the column x density of the liquid x gravitational field strength
why does pressure increase with the height of the column of liquid?
due to the weight of the column of water above
what does a partially or totally submerged object experience?
a greater pressure on the bottom surface than on the top surface creating a resultant force upwards (UPTHRUST)
which factors influence floating and sinking?
the mass and volume of the object
mass-to-volume ratio of the object
Density of the water
density of object is less than water.
how is air pressure created and how does it change with altitude?
Air pressure is caused by the weight of the air molecules above
As altitude rises, air pressure drops
