Melting is a process that causes a substance to change from a solid to a liquid. Melting occurs when the molecules of a solid speed up enough that the motion overcomes the attractions so that the molecules can move past each other as a liquid.
The Purpose of Work. âWe work to have leisure, on which happiness depends.â So said Aristotle, quoted by Notre Dame philosopher Gary Gutting to explain âWhat Work Is Forâ in a recent article for The New York Times. Luther countered this medieval view of workâwhich is coming back into style in our consumerist cultureâwith his doctrine of vocation.
The physics definition of work is: The unit of work is the unit of energy, the joule (J). 1 J = 1 N m. Work can be either positive or negative: if the force has a component in the same direction as the displacement of the object, the force is doing positive work.