Editor's desk - Own laws of work

Work is a fundamental concept of mechanical engineering and has many applications. Understanding how work is calculated and the different types of work can help us better understand physical processes and provide insights into complex problems.
Work is defined as the result of a force acting on an object, causing it to move along the line of action of force. It is also defined as the process of transferring energy through the application of force on an object, resulting in its displacement.

Work is done when energy is transferred from one object to another. In other words, work is when a force acts on something that undergoes a displacement from one position to another. Forces can vary as a function of position, and displacements can be along various paths between two points. The increment of work (dW) done by a force acting through an infinitesimal displacement can be defined as the dot product of force () and displacement () vectors.
The dot product can be expressed in terms of...

The total work done on an object acted upon by multiple forces can be computed using two methods that give the same result. In one method, the work done by each force is first calculated. Then, those values are summed algebraically to calculate the total work done by all the forces. In the second method, the net force is first calculated by a vector sum of all the forces. Then, the work done by this force is obtained.
Since forces perpendicular to the displacement do no work, they do not...

As a system undergoes a change, its internal energy can change, and energy can be transferred from the system to the surroundings, or from the surroundings to the system.

According to Newton’s second law of motion, the sum of all the forces acting on a particle (net force) determines the rate of change in the momentum of the particle (motion). Therefore, we should consider the work done by all forces acting on a particle, or the net work, to see its effect on the particle’s motion.
The work-energy theorem equates work done by all the forces on an object to the change in its kinetic energy. The theorem can be used to calculate work done by a force...

The work done by an external force on a particle changes its kinetic energy. However, internal forces must also be considered for a system of interacting particles. The potential energy formulation helps formulate the effect of internal forces. The net work done by an external force can be written in terms of the total change of mechanical energy, which includes both kinetic and potential energies.
In the presence of a non-conservative opposing force, like friction, some part of the work done...