CH 8 : pressure Flashcards
(17 cards)
what is pressure
pressure is force that acts perpendicularly to the surface of an object
factor that affects the pressure
- force = the ^ the force , the ^ the pressure - surface area = the bigger the surface area , the smaller the pressure *** larger SA = smaller pressure *** smaller SA = larger pressure
symbol for pressure
N/m2 or Pa ( Pascal )
formula for pressure
force (N)
________
surface area ( m2 )
gas pressure
based on the kinetic theory of gas
explain the gas pressure based on the kinetic theory of gas
P1 = the air molecules move freely/ randomly collide with the wall of its container P2 = the frequency of collision between the air molecules and wall of its container will produce air pressure (the force that pushes against the wall )
what is the factor that affect the gas pressure
- volume ( the higher the volume, the lower the pressure )
- temperature ( the higher the temperature, the higher the pressure )
when the container is compressed , what will happen
the volume in the container decreases and cause the frequency of collision between the air molecules and the wall of its container to become more often and hence the air pressure increases
what will happen when the temperature in the container increases
the air molecules will gain more energy and collide more frequently with the wall of its container and hence the air pressure increases
what is the atmospheric pressure
the pressure that exerted by the atmosphere on the surface of the Earth and all objects on the earth
air pressure moves from which pressure to what pressure
high pressure —> low pressure
SUCKER HOOK
what will produce when a\the air s forced out
=low-pressure area is produced when the sucker hook is pressed.
= the higher atmospheric pressure presses on the hook and causes it to stick at the wall
when the plunger is pushed or presed downwards, what will happen
= the air inside it is forced out and produce a low-pressure area
= the higher pressure outside presses the huck and make it stick to the surface of sink
= when the plunger pulled upwards, the higher pressure pushes out the blockage stuck
what is altitude
the height above the sea level
what is the relationship between the altitude and pressure
the higher the altitude , the lower the pressure
Why atmospheric pressure increases as altitidue decreases
Due to graitational attraction
Why the liquid experience the pressure
Because the weight of the liquid acts on the whole object and cause the pressure
