PART 4 Resources
Energy is the potential for performing work and it is measured in the same unit: J (joule). Energy ﬂow rate is measured by the unit W (watt), which is the ﬂow of 1 J per 1 s (J/s). Watt also measures the ability to carry out work (J) in unit time (s), i.e. power. As energy and work have the same unit (J), power and energy ﬂow rate have the same physical dimension, thus the same unit (W).