Question

the rate at which electrical energy is used

Answer 1

The rate at which energy is used is called "power". The SI unit for power is the Watt. One watt is equal to one Joule per Second. In other words, a 100 W light bulb uses 100 Joules in 1 second. If you have a DC circuit you can find power with one of the following three formulas: \[P = IV, P= I ^{2}R, P=\frac{V ^{2}}{ R }\] where P is the power in Watts, I is the current in Amperes, and V is the Voltage in Volts.