There is very little water pushing down on the water at the top of the tube.
#Lots more water pushing down at the bottom.=pressure at the bottom is higher.
water, air, and other fluids, pressure increases with depth.
The pressure of airat sea levelis called one atmosphere(1 atm).
=101.3Kpa
#with each 10m go deeper in the waterthan sea level, pressure goes up by 1 atm.(1 atm =10000kgpushing down on the area of 1 square meter)
Buoyancy
Buoyancy is the tendency for objects to rise or float in a fluid.
Buoyancy occurs because of differences in densityof the object and the fluid.
Buoyant force: Objects rise or float in a fluid because the fluid pushes up on them with a force.
Convection
The buoyant force us what makes heated air rises.
#The density of the heated air is less then the desity of the cooler air.
so the heated air rises, the cooler air sinks.
This transfer of heat throught the flow of a heated fluid is called convection.
#When the buoyant and the force of gravity are unbalanced, object will move direction to the larger force.
#When the two forces are balanced, no motion will occur.
examples:
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