1.8 Pressure Flashcards
(9 cards)
What is pressure?
Pressure is the force per unit area.
What is the formula for pressure?
The formula for pressure is:
P = F/A
Where:
P is pressure (in pascals, Pa)
F is force (in newtons, N)
A is area (in square meters, m²)
Where do we see pressure in real life?
Pressure is seen in various real-life situations, such as:
Pushing a door: The force you apply on the door is spread over the area of your hand.
Standing on the floor: Your body weight is distributed over the area of your feet.
Nail or thumb pin: The sharp tip of a nail or thumb pin exerts a high pressure on the surface it is pushed into because of its small area.
What is the unit of pressure?
The unit of pressure is the pascal (Pa).
How is pressure exerted in liquids?
In liquids, pressure is exerted from all directions.
This means that the pressure in a liquid acts equally in every direction, and it increases with depth. The pressure at a given point in a liquid depends on the density of the liquid, the gravitational field strength, and the depth.
How does force act on the surface of an object?
Force acts at 90 degrees (perpendicular) to the surface of an object.
This is the direction in which pressure is applied, and it is the typical way force is exerted when it comes to surface interactions, such as when an object is in contact with a surface.
What is the formula for pressure in a liquid?
The formula for pressure in a liquid is:
P=ρgh
Where:
P = pressure at depth (Pa)
ρ = density of the liquid (kg/m³)
g = gravitational field strength (9.8 N/kg)
h = height or depth of the liquid (m)
What is the formula for change in pressure in a liquid?
The formula for the change in pressure in a liquid is:
ΔP=ρgΔh
Where:
ΔP = change in pressure (Pa)
ρ = density of the liquid (kg/m³)
g = gravitational field strength (9.8 N/kg)
Δh = change in height or depth of the liquid (m)
