1.1: An Introduction to Mechanics
Humans have been making ships, shelters, pyramids, weapons, agricultural equipment, and many more items without recording the process or theory behind them for centuries. It would be challenging to document the evolution of mechanics from its origin to the present.
According to records, the history of mechanics starts with Aristotle (384–322 BC). He related mechanics to physical theory, aiming for a universal synthesis.
Newton defined mechanics as the branch of physical science that studies the state of an object at rest or in motion under the action of forces. Mechanics is a fundamental area of physics with significant applications in various branches of engineering and science. The study of mechanics is essential for understanding the motion of everyday objects, the behavior of machines and devices, and the functioning of different systems.
Rigid body mechanics is a branch of mechanics that deals with objects in which deformation is negligible under the action of forces. Rigid body mechanics can be divided into the branches of statics and dynamics. Statics deals with the state of objects at rest, whereas dynamics deals with objects in motion. Dynamics is further divided into kinematics and kinetics, with the former neglecting the forces responsible for the motion and the latter considering them.
Deformable body mechanics, on the other hand, focuses on the deformation of an object under the action of forces. Understanding the behavior of materials, such as those used in construction or manufacturing, and the design and analysis of different structures is crucial.
Fluid mechanics is the study of the motion and forces of fluids. It is a vast field, and it is classified into compressible and incompressible fluids, depending on their behavior. Fluid mechanics has many practical applications and is used in designing and analyzing various systems, such as hydraulic or pneumatic systems, fluid transportation systems, and chemical processing equipment.
Many structures and machines are designed and analyzed based on the principles of mechanics. For instance, the design of buildings, bridges, and other structures depends on principles of mechanics to assess the strength of the materials, the forces of gravity, and the movement of the earth. Mechanics principles are also used in the design of automobile components, such as leaf springs and hydraulic braking systems, crane hooks, industrial robots, and pneumatic nail guns.
