WORK(a complete discription)

Defination: - “The product of force and displacement ( in the direction of force ), during which the force is acting, is defined as work.”
The displacement may not be in the direction of the applied force in all cases. The displacement, d, makes an angle θ with the applied force, F. According to the definition of force,
Work, W = force × displacement in the direction of the force
               = F ( d cos θ )
               = ( F cos θ ) ( d )
               = ( the component of force in the direction of displacement ) × ( displacement )
Scalar product of two vectors: -The scalar product of two vectors,A and B , also known as the dot product, is written by
putting a dot ( ⋅ ) between the two vectors and is defined as: A ⋅ B = lAl lBl cos θ = A B cos θ, where θ is the angle between the two vectors.
 kinetic energy: -     “The capacity of a body to do work, by virtue of its motion, is known as the kinetic energy of the body.”
More the speed of the object, more is its kinetic energy. The net force acting on a body produces acceleration or deceleration in its motion thereby changing its velocity and kinetic energy. Also, work is done by the net force on the body while causing its displacement. The work, W, done by the force, F, on a particle of mass, m, causing acceleration,a and displacement,d is given by
W = F ⋅ d = ma ⋅ d … … … … … ( 1 )