Fluid Mechanics

Fluid mechanics has applications in mechanical, aerospace, civil, chemical, and biomedical engineering, as well as geophysics, oceanography, meteorology, astrophysics, and biology.

Fluid mechanics is the branch of physics concerned with the mechanics of fluids (liquids, gases, and plasmas) and the forces on them.

Computational fluid dynamics (CFD) is a modern discipline devoted to addressing unsolved problems in fluid mechanics, typically using numerical methods and computers.

Fluid mechanics can be divided into fluid statics, the study of fluids at rest; and fluid dynamics, the study of the effect of forces on fluid motion.

Fluid dynamics is considered an active field of research because many problems are partly or wholly unsolved and are best addressed by numerical methods, typically using computers.

Surface tension in liquids is primarily caused by the greater attraction of liquid molecules to each other (cohesion) than to the molecules in the air (adhesion), resulting in an inward force on the surface molecules causing the liquid to contract and a tangential force parallel to the surface known as surface tension.

Surface tension allows objects with higher density than water to float on a water surface without becoming submerged by creating an upward force that opposes the force of gravity, keeping the object afloat.

The analogy used to describe the behavior of a liquid's surface due to surface tension is that the liquid behaves as if its surface were covered with a stretched elastic membrane.

The tangential force in surface tension is a force parallel to the surface of the liquid, which is the result of the inward force on the surface molecules causing the liquid to contract.

It is cautioned that the analogy of a stretched elastic membrane should not be taken too far when describing surface tension because the tension in an elastic membrane depends on the amount of deformation, while surface tension does not have the same dependency.