What is the Electrical power for a lightbulb?

Answer 1

The power rating for a light bulb (like "40 W") tells how much electrical power the light bulb uses. All of the power used by the bulb is either converted into light or heat. In an incandescent bulb, most of the energy becomes heat. In a fluorescent bulb, more of it becomes light.

Answer 2

On a lightbulb, there is a number that is followed by a W. That is the number of watts the lightbulb uses. A watt is a measure of how much energy the bulb uses every second. The more watts, the more energy the lightbulb uses every second. For you calculus types: Power is the derivitive of Work with respect to time