High Quality Content by WIKIPEDIA articles! In physics, mechanical work is the amount of energy transferred by a force acting through a distance. Like energy, it is a scalar quantity, with SI units of joules. The term work was first coined in 1826 by the French mathematician Gaspard-Gustave Coriolis.According to the work-energy theorem if an external force acts upon a rigid object, causing its kinetic energy to change from Ek1 to Ek2, then the mechanical work (W) is given by: W = Delta E_k = E_{k2} - E_{k1} = tfrac12 m (v_2^2 - v_1^2) ,! where m is the mass of the object and v is the object's velocity.