Liquid pressure and upthrust and atmospheric pressure

what is the equation for liquid pressure

Liquid pressure = density x gravitational field strength x depth

p = hpg

what causes an object to sink

if the upthrust on an object is smaller than the object's weight or if the object has a density more than the density of the fluid it is immersed in

what is upthrust

The upwards force exerted by a fluid on a submerged object

How does upthrust work?

- greater force acting on the bottom of the object than the force acting on the top of the object

- resultant force acting upwards which pushes the object up

why is pressure higher closer to the earth

because the density of gas particles is highest near the earth's surface so an object closer to earth will feel more pressure as there are more particles and so a higher number of collisions

why must mountain climbers carry oxygen

because the air is very thin so there's not enough oxygen to breathe in

why is air pressure smaller as you go higher

at a higher elevation the gas particles are more spread out and so they generate less pressure

why does pressure increase as you go below sea level

an object at sea level will have lots more particles around it so there'll be more collisions with the surface of the sea object, than there would with the object that's really high up and more collisions = a greater force= high pressure