P11 Flashcards
WHAT IS PRESSURE?
Force exerted per unit of area
WHAT ARE THE TWO UNITS PRESSURE CAN BE MEASURED IN?
Pa- Pascals
N/m2
WHAT IS THE EQUATION FOR PRESSURE?
Pressure = Force/ Area
A LIQUID FLOWS UNTIL…
Pressure along any horizontal line is constant
WHAT IS THE RULE FOR PRESSURE IN LIQUIDS?
That the further you go down, greater height of liquid above so greater pressure
WHAT IS THE EQUATION FOR PRESSURE IN LIQUID?
Pressure (Pa) = height of liquid above point (m) x Denisty of liquid (kg/m2) x 9.8 N/kg
WHAT IS PRESSURE IN LIQUID DUE TOO?
surrounding water molecule colliding with each other and exerting force
WHAT DOES ARCHIMEDES PRINCIPLE STATE?
when an object is placed in fluid it displaces a volume of fluid equal to its own volume
HOW IS UPTHRUST PRODUCED?
pressure in liquids decreases with depth so pressure exerted by fluid is greater at bottom of an object then the top which means there is an overall upwards force
WHEN DOES AN OBJECT FLOAT?
when weight is more than object or when object is less dense than liquid
WHEN DOES AN OBJECT SINK?
when upthrust is resultant to weight or object more dense than liquid
WHAT IS THE ATMOSPHERE?
a layer around the earth
WHAT IS ATMOSPHERIC PRESSURE?
atmospheric pressure is due to air molecules colliding with surfaces
WHAT HAPPENS AT HIGHER ALTITUIDE?
Less weight of air above so less pressure and less dense air so fewer particles collide
