Definitions- Theory of Machines

Definition

The subject Theory of Machines can be described as that branch of engineering science which focuses on the study of relative motion between different components of a machine and the forces acting on them. The understanding of this subject is extremely important for engineers while designing the various machine parts.

Note: A machine is a device that receives energy in a usable form and converts it to perform a specific kind of work.

Sub-divisions of Theory of Machines

The Theory of Machines is generally divided into the following four major branches:

  1. Kinematics: This branch deals with the motion of machine parts without considering the forces causing that motion. It focuses only on relative movement between components.
  2. Dynamics: This part of Theory of Machines studies the forces and their effects acting on machine elements while they are in motion.
  3. Kinetics: This branch examines the inertia forces that arise due to the combined effect of mass and motion of machine parts.
  4. Statics: This branch focuses on the forces acting on machine members at rest. Here, the motion is absent and the mass of parts is considered negligible.

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