In the 8th century, a priest in Lanciano, Italy was experiencing doubts about the real presence of Jesus in the Eucharist. In the middle of saying Mass, he said the words of consecration (âThis is my body,â âThis is my blood) and saw the bread and wine transform into real human flesh and blood.
Energy is usually defined as the ability to do work. This is an anthropocentric and utilitarian perspective of energy; however, it is a useful definition for engineering where the aim of machines is to convert energy to work.
Now we can give our first scientific definition of energy: The energy of an object, or of a system, is how much work the object or system can do on some other object or system. In other words, energy measures the capability of an object or system to do work on another system or object.