A fluid is a state of matter that yields to sideways or shearing forces. Liquids and gases are both fluids. Fluid statics is the physics of stationary fluids. Density is the mass per unit volume of a ...A fluid is a state of matter that yields to sideways or shearing forces. Liquids and gases are both fluids. Fluid statics is the physics of stationary fluids. Density is the mass per unit volume of a substance or object while pressure is the force per unit perpendicular area over which the force is applied. Pressure due to the weight of a liquid of constant density is given by the product of the liquid's depth, density, and acceleration due to gravity.
