Define work done write expression for work done. Also write the factors affecting the work.
Answers
Answer:
We use terms such as overworked and hard workers to describe the effort put by a person. But what is the meaning of work and how do we quantify it? In this article, we will learn the definition of work in terms of physics and the factors on which work depends.
Defining Work
The scientific definition of work is different in many ways from its everyday meaning. The definition of work in physics reveals its relationship to energy – whenever work is done, energy is transferred.
For a work to be done, in a scientific sense, a force must be exerted and there must be displacement in the direction of the force. With this said, we can say that
Work is the product of the component of the force in the direction of the displacement and the magnitude of this displacement.
Mathematically, the above statement is expressed as follows:
W = (F cos θ) d = F. d
Where,
W is the work done by the force.
F is the force, d is the displacement caused by the force
θ is the angle between the force vector and the displacement vector
The dimension of work is the same as that of energy and is given as, [ML2T–2].
Unit of Work
The SI unit of work is the joule (J), which is defined as the work done by a force of 1 Newton in moving an object through a distance of 1 meter in the direction of the force.
work
A weightlifter lifts a barbell weighing 25 kg and displaces it from the ground by 2 m. Here, the work done upon the barbell is against gravity.
The work done upon the weight against gravity can be calculated as follows:
Work Done = (Mass × acceleration due to gravity) × Displacement
= (25 × 9.8) × 2 J