All of us use words like work, power and energy.  In this unit we will define their meaning in the context of physics; we will evaluate the need for such exactitude in order to tackle many facts of daily life; and investigate new applications; we will verify how the calculation of work (W), of the power (P) produced by a machine or the measurement of energy (E) consumed or stored, are very useful for maintaining and developing the society in which we live.

Let's have a look at the ideas we already have about work, power and energy.