I had a couple of lessons about pressure at my high school last week and my teacher taught us some principles but not why they are true.
Why is this statement true: Pascal's principle : Pressure applied to an enclosed fluid is transmitted undiminished to every part of the fluid, as well as to the walls of the container.
Why is pressure transmitted? Why not force?
Why is this statement true: Archimedes principle : An object that is partly or completely submerged in a fluid will experience a buoyant force equal to the weight of the fluid the object displaces.
Why is the buoyant force equal to the weight of the fluid the object displaces? And why is there a buoyant force at all? Why do less dense things float and more dense things sink?
Bernoulli's principle states that an increase in the speed of the fluid occurs simultaneously with a decrease in pressure or a decrease in the fluids potential energy. Why is this true? And what is a fluids potential energy?
I was also told that pressure will act in all directions equally at a certain depth. Why is this? Why is the pressure on the wall of the container the same as the pressure on an object at the same depth?
I was also wondering why fluids exert pressure on their container (why do fluids take the shape of their container?).
Why is there more pressure in a can when the gas inside is compressed?
This pressure stuff confuses and frustrates me. Any help is appreciated.
