>>14191587Not this
>>14191539 guy but he is correct. How hard it is to move your hand through a medium is dependent upon the drag that medium exerts on your hand as it tries to move through it, not the pressure. Think of a cube sitting on a surface. If you apply equal and opposite forces to the cube, these forces don't affect your ability to move the cube, because they cancel out. It's the same thing with fluid pressure, it is applied to every surface of an object, and you can prove mathematically that the net pressure force is zero on an object of arbitrary shape.
The two types of drag your hand would encounter in both air and water are viscous drag, and form drag. You can think of viscous drag like friction between the fluid and your hand. It's influenced by the viscosity of the fluid medium, and the speed and surface area of the object. The higher the viscosity, the higher the friction. Water has a viscosity about 50 times that of air. When you move an object through a fluid, the pressure on the front facing side increases and the pressure on the back decreases, which leads to an imbalance in pressure called the form drag. The form drag is influenced by the density of the fluid medium, and the shape and speed of the object. A higher fluid density results in larger form drag. Water is about 1000 times denser than air.
